A while ago I played with
https://www.bitaddress.org/ and printed a couple of nicely colored paper wallets that look like bank notes. Every time I talked to someone about bitcoin I simply gave him one of these (unfunded). Public key, private key, no this is not safe but just a thing to play, blabla.
Seeing these bank notes makes quite an impression on people - seeing is believing. And if they take it is a reminder to do some research about it at home. Of course if you like you can also send some coins to the paper wallet to show off.
There is a thread about tech details and stuff here:
https://bitcointalk.org/index.php?topic=43496It is possible to fund the wallets using several android clients. Redeeming is currently only possible with the mtgox client as far as I know (but funding with it is currently broken).