How do I make a Rake Task run after all other tasks? (i.e. a Rake AfterBuild task)

I'm new to Rake and using it to build .net projects. What I'm interested in is having a Summary task that prints out a summary of what has been done. I want this task to always be called, no matter what tasks rake was invoked with.

Is there an easy way to accomplish this?

Thanks

Update on the question, responding to Patrick's answer what I want is the after task to run once after all other tasks, so the output I want is:

task :test1 do 
  puts 'test1'
end

task :test2 do 
  puts 'test2'
end

Rake::Task.tasks.each do |t|
    <Insert rake magic here>
#  t.enhance do 
#    puts 'after'
#  end
end

$ rake test1
test1
after

$rake test2
test2
after

$rake test1 test2  
test1
test2
after

and if

task :test3 =>[:test1, :test2]
   puts 'test3'
end

    $rake test3
test1
test2
test3
after

Even though the bounty is gone, any further help much appreciated. (Sadily I don't think that I can offer another bounty.)