diff --git a/app/controllers/graders_controller.rb b/app/controllers/graders_controller.rb
--- a/app/controllers/graders_controller.rb
+++ b/app/controllers/graders_controller.rb
@@ -1,7 +1,13 @@
 class GradersController < ApplicationController
 
-  
-  before_filter :authorization
+  before_filter :admin_authorization
+
+  verify :method => :post, :only => ['clear_all'], 
+         :redirect_to => {:action => 'index'}
+
+  def index
+    redirect_to :action => 'list'
+  end
 
   def list
     @grader_processes = GraderProcess.find(:all, 
@@ -15,4 +21,31 @@
     redirect_to :action => 'list'
   end
 
+  def clear_all
+    GraderProcess.find(:all).each do |p|
+      p.destroy
+    end
+    redirect_to :action => 'list'
+  end
+
+  def view
+    if params[:type]=='Task'
+      redirect_to :action => 'task', :id => params[:id]
+    else
+      redirect_to :action => 'test_request', :id => params[:id]
+    end
+  end
+
+  def test_request
+    @test_request = TestRequest.find(params[:id])
+  end
+
+  def task
+    @task = Task.find(params[:id])
+  end
+
+  def submission
+    @submission = Submission.find(params[:id])
+  end
+
 end
diff --git a/app/controllers/user_admin_controller.rb b/app/controllers/user_admin_controller.rb
--- a/app/controllers/user_admin_controller.rb
+++ b/app/controllers/user_admin_controller.rb
@@ -1,6 +1,6 @@
 class UserAdminController < ApplicationController
 
-  before_filter :authenticate, :authorization
+  before_filter :admin_authorization
 
   def index
     list
diff --git a/app/helpers/application_helper.rb b/app/helpers/application_helper.rb
--- a/app/helpers/application_helper.rb
+++ b/app/helpers/application_helper.rb
@@ -13,7 +13,7 @@
       append_to menu_items, '[Problem admin]', 'problems', 'index'
       append_to menu_items, '[User admin]', 'user_admin', 'index'
       append_to menu_items, '[User stat]', 'user_admin', 'user_stat'
-      #append_to menu_items, '[Graders]', 'graders', 'list'
+      append_to menu_items, '[Graders]', 'graders', 'list'
       append_to menu_items, '[Site config]', 'configurations', 'index'
       menu_items << "<br/>"
     end
@@ -72,4 +72,12 @@
 TITLEBAR
   end
 
+  def read_textfile(fname,max_size=2048)
+    begin
+      File.open(fname).read(max_size)
+    rescue
+      nil
+    end
+  end
+
 end
diff --git a/app/helpers/test_helper.rb b/app/helpers/test_helper.rb
--- a/app/helpers/test_helper.rb
+++ b/app/helpers/test_helper.rb
@@ -1,11 +1,2 @@
 module TestHelper
-
-  def read_textfile(fname,max_size=2048)
-    begin
-      File.open(fname).read(max_size)
-    rescue
-      nil
-    end
-  end
-
 end
diff --git a/app/models/grader_process.rb b/app/models/grader_process.rb
--- a/app/models/grader_process.rb
+++ b/app/models/grader_process.rb
@@ -1,7 +1,5 @@
 class GraderProcess < ActiveRecord::Base
   
-  belongs_to :task
-
   def self.find_by_host_and_pid(host,pid)
     return GraderProcess.find(:first, 
                               :conditions => { 
@@ -16,6 +14,7 @@
       grader.mode = mode
       grader.active = nil
       grader.task_id = nil
+      grader.task_type = nil
       grader.save
     else
       grader = GraderProcess.create(:host => host, 
@@ -33,13 +32,15 @@
   
   def report_active(task=nil)
     self.active = true
-    self.task = task
+    self.task_id = task.id
+    self.task_type = task.class.to_s
     self.save
   end                
 
   def report_inactive()
     self.active = false
-    self.task = nil
+    self.task_id = nil
+    self.task_type = nil
     self.save
   end                
 
diff --git a/app/models/task.rb b/app/models/task.rb
--- a/app/models/task.rb
+++ b/app/models/task.rb
@@ -1,5 +1,7 @@
 class Task < ActiveRecord::Base
 
+  belongs_to :submission
+
   STATUS_GRADING = 0
   STATUS_INQUEUE = 1
   STATUS_COMPLETE = 2
diff --git a/app/views/graders/_grader.html.haml b/app/views/graders/_grader.html.haml
--- a/app/views/graders/_grader.html.haml
+++ b/app/views/graders/_grader.html.haml
@@ -1,9 +1,11 @@
 
 %td= grader.host
 %td= grader.pid
+%td= grader.mode
 %td= grader.updated_at.strftime("%H:%M:%S") if grader.updated_at!=nil
+%td= grader.task_type
 %td
   - if grader.task_id==nil
-    \-
+    idle
   - else
-    = grader.task_id
+    = link_to "#{grader.task_id}", :action => 'view', :id => grader.task_id, :type => grader.task_type
diff --git a/app/views/graders/_grader_list.html.haml b/app/views/graders/_grader_list.html.haml
--- a/app/views/graders/_grader_list.html.haml
+++ b/app/views/graders/_grader_list.html.haml
@@ -3,7 +3,9 @@
   %tr
     %th host
     %th pid
+    %th mode
     %th last updated
+    %th type
     %th task
   - grader_list.each do |grader|
     - if grader.active
diff --git a/app/views/graders/list.html.haml b/app/views/graders/list.html.haml
--- a/app/views/graders/list.html.haml
+++ b/app/views/graders/list.html.haml
@@ -3,6 +3,9 @@
 
 %h2 (Under Experiments)
 
+- form_for :clear, nil, :url => {:action => 'clear_all'} do |f|
+  = submit_tag 'Clear all data'
+
 %h3 Current graders
 
 = render :partial => 'grader_list', :locals => {:grader_list => @grader_processes}
diff --git a/app/views/graders/submission.html.haml b/app/views/graders/submission.html.haml
new file mode 100644
--- /dev/null
+++ b/app/views/graders/submission.html.haml
@@ -0,0 +1,22 @@
+%h1= "Submission: #{@submission.id}"
+
+%p
+  User:
+  = "#{@submission.user.login}"
+  %br/
+  Problem: 
+  - if @submission.problem!=nil
+    = "#{@submission.problem.full_name}"
+  - else
+    = "(n/a)"
+  %br/
+  = "Number: #{@submission.number}"
+  %br/
+  = "Submitted at: #{format_short_time(@submission.submitted_at)}"
+
+%b Source code (first 10kb)
+%div{:style => "border: 1px solid black; background: lightgrey"}
+  - if @submission.source
+    %pre
+      = truncate(@submission.source,10240)
+
diff --git a/app/views/graders/task.html.haml b/app/views/graders/task.html.haml
new file mode 100644
--- /dev/null
+++ b/app/views/graders/task.html.haml
@@ -0,0 +1,15 @@
+%h1= "Task: #{@task.id}"
+
+%p
+  User:
+  = "#{@task.submission.user.login}"
+  %br/
+  Status: 
+  = "#{@task.status_str} (at #{format_short_time(@task.updated_at)})"
+  %br/
+  = "Submission: #{@task.submission_id}"
+  - if @task.submission !=nil
+    = link_to '[view submission]', :action => 'submission', :id => @task.submission.id
+  %br/
+  = "Submitted at: #{format_short_time(@task.created_at)}"
+  %br/
diff --git a/app/views/graders/test_request.html.haml b/app/views/graders/test_request.html.haml
new file mode 100644
--- /dev/null
+++ b/app/views/graders/test_request.html.haml
@@ -0,0 +1,40 @@
+%h1= "Test Request: #{@test_request.id}"
+
+%p
+  User:
+  = "#{@test_request.user.login}"
+  %br/
+  Problem: 
+  - if @test_request.problem!=nil
+    = "#{@test_request.problem.full_name}"
+  - else
+    = "(n/a)"
+  %br/
+  = "Submission: #{@test_request.submission.number}"
+  = link_to '[view submission]', :action => 'submission', :id => @test_request.submission.id
+  %br/
+  = "Test submitted at: #{format_short_time(@test_request.submitted_at)}"
+  %br/
+  = "Execution time: #{@test_request.running_time} s."
+  %br/
+  = "Memory usage: #{@test_request.memory_usage}kb"
+  %br/
+  %b= @test_request.exit_status
+  %br/
+
+- if @test_request.compiler_message!=nil and @test_request.compiler_message!=''
+  %b Compiler Message
+  %div{:style => "border: 1px solid black; background: lightgrey"}
+    = simple_format(truncate((@test_request.compiler_message or ''),200))
+
+%b Input (first 2kb)
+%div{:style => "border: 1px solid black; background: lightgrey"}
+  - if @test_request.input_file_name!=nil
+    = simple_format(read_textfile(@test_request.input_file_name,2048))
+
+%b Output (first 2kb)
+%div{:style => "border: 1px solid black; background: lightgrey"}
+  - if @test_request.output_file_name!=nil
+    = simple_format(read_textfile(@test_request.output_file_name,2048))
+  - else
+    (no output)
diff --git a/db/migrate/033_add_task_type_to_grader_processes.rb b/db/migrate/033_add_task_type_to_grader_processes.rb
new file mode 100644
--- /dev/null
+++ b/db/migrate/033_add_task_type_to_grader_processes.rb
@@ -0,0 +1,9 @@
+class AddTaskTypeToGraderProcesses < ActiveRecord::Migration
+  def self.up
+    add_column 'grader_processes', 'task_type', :string
+  end
+
+  def self.down
+    remove_column 'grader_processes', 'task_type'
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -9,7 +9,7 @@
 #
 # It's strongly recommended to check this file into your version control system.
 
-ActiveRecord::Schema.define(:version => 32) do
+ActiveRecord::Schema.define(:version => 33) do
 
   create_table "announcements", :force => true do |t|
     t.string   "author"
@@ -42,6 +42,7 @@
     t.datetime "created_at"
     t.datetime "updated_at"
     t.integer  "task_id"
+    t.string   "task_type"
   end
 
   add_index "grader_processes", ["host", "pid"], :name => "index_grader_processes_on_ip_and_pid"