Tom Ward is an electronic product designer (his business card says so) who has made a business card that autodials his phone number. You slap the corner of the card (which contains a small speaker) against the mouthpiece of your phone and the card emits "a series of DTMF audio tones to automatically dial the phone number you have programmed." He has a post on instructables if you're interesting in making them yourself, and he says he's got the price down to about $2.00 apiece when making them in large batches. I'm definitely going to make some, except I'm not going to program my real number. Nope, I'm going to use some long-ass-distance international number in China. Then everyone I give my card to will have an expensive phone bill for calling China! Oh the hilarity, I can't wait. Of course my business is going to go straight to shit because I've alienated all my customers, but that's a small price to pay for such a great practical joke.
Brilliant Autodialling Business Card [ohgizmo]