We like jokes and here is a little helper for those who are like us.
If you want to make fun of your colleagues (and are risky enough to take the consequences), you can install Fools Day TeamCity plugin.
Read more at: http://teamcitydev.blogspot.com/2008/04/fools-day-teamcity-plugin.html
And today (on April, the 1st) , you can also see it in action on http://teamcity.jetbrains.com
The JetBrains TeamCity Team