This is a very nice trick that you can use to impress your friends. StumbleUpon has a little “window” that you can use to post an error message of your own.

Here is an example :

To do your own custom error page at StumbleUpon and impress your friends you just have to use this url:

http://www.stumbleupon.com/error.php?error=XXX

Where XXX stands for your message. Click here for an example.

Enjoy