It's already a classic but you can't beat a pen that writes as smoothly, even upside down or underwater. There maybe aren't that many applications for the latter, unless you're an oceanographer, but it's a cool feature and one which undoubtedly accounted for how many times mine was stolen by jealous friends.

An out of this world gift for the person who has everything. Brilliant compact design for the wallet or handbag. Writes upside down, under water and in extreme temperatures. Well what more can you ask for. Now you can write all of your christmas cards in the bath. Wow! (via Fisher Space Pen)