Elektor again :
ever had frozen car locks.
the elektor car lock defrost circuit. never be frozen out of your car again.
simply plug it into the cigar lighter socket of the car, and it instantly defrosts the mechanism.
The great thing, is it actualy would have worked, as it was a large transistor / diode bonded to a spareKey, which got hot.
I seem to recall Compute magazine had a series of April Fools ads in the early 80's. In particular, I remember an auto eject system for floppy disks that at the slightest sign of a computer crash would eject your floppies at high speed. (Remember when a computer crash could zap files on your floppies)? Of course, this system did have a problem of injuring anyone in the path of the ejected floppy, or embedding the floppies in brick walls. :)