aggregates twitter, pownce and facebook with a lot more rss feeds to social networking sites coming. See the Vote page for what they're working on. Contact me for a beta invite
"PownceFS is a Fuse filesystem that mounts your friends’ files from Pownce as a local filesystem. Given a mountpoint, it fakes a directory for each of your friends and puts all the files they’ve uploaded inside. "
Ping.fm is a simple service that cuts out the middle man when it comes to posting to your social services such as Facebook, Twitter, Jaiku, Tumblr and Pownce with more being added soon.