The Joker Birthday card is possibly the world’s greatest birthday card. Once opened, it will start singing Happy Birthday… and never stop! Well, “never” means until the batteries run out (about 3 hours) or until your friend tears it up. It’s. Brilliant!

The card is first delivered to you in a “safe mode”, which allows you to write your message without suffering the same fate. When it’s ready, just pull out a little tab to arm it. When your friend gets it, it’ll be primed for some great birthday fun. Here are some tips to get the most out of it:

• When you send your card, write something really special in it. The nicer the message the harder it will be for them to tear it up. If the kids send a card to grandma there’s no way she can tear that up.

• When you give your card at the party, be the first one. This way the card will not only drive your friend crazy as they open other presents, everyone else at the party who’s in on the joke can enjoy it too!

• Give the card to a friend staying at a hotel, preferably after dinner. This way when they open it they’ll have no escape when it’s still singing at 1am in the morning.

It’s pure evil genius, but of the harmless sort; these make the best kind of pranks. You can get yours for a $15 on their more than fully funded Kickstarter.

[ Project Page ] VIA [ Geekologie ]