On forbes.com today, there was a little thing on "Gadgets you can't buy"
featuring things like a drink cooler make with cooling systems for computers, a computer controled etch-a-sketch, and others.
One that popped out to me was a home made external iPod battery
in an altoids tin.
The tin/battery can be seen here:
http://www.chrisdiclerico.com/mt/archives/001572.php