Bluetooth
I just compiled and installed GNOME Bluetooth. Nice piece of software, that allows me to send and receive files from and to my cellphone. It doesn't do much more than that at this time, unfortunately; stuff such as Evolution and/or multisync integration would be nice. But then, there's probably a reason why it hasn't been declared finished yet.
I also tried to get a hold of the Bluetooth spec. It seems to be only semi-public, though; you need to be registered to be able to access it. I'm allergic to that, especially if I don't actually need it, but have only casual interest, as is the case now.
Though one thing would be nice: a bluetooth headset implementation in software, which would allow me to pick up my phone while hacking, without having to go look for it. That'd be nice for a change; and I'm sure it could have other uses, too -- asterisk anyone?