Quote Originally Posted by ensign_lee
And don't do like some evil people do:

Switch the 3h to look like Ah or something like that on your buddy's computer. Rinse, repeat with other cards. It will fuck him up like none other.
That's the worst thing I've ever heard, surpassing the MS Word trick of adding your own personal creative autosubstitutes (i.e. 'the' --> 'penis') and the trick where you take a screenshot of someone's desktop, then erase all their icons and use the screenshot as the background image.