EtherPad
Late in 2009 Google acquired AppJet, the company responsible for the popular collaberative Web-based text editing tool, Etherpad.
Presumably this is to beef up Wave’s feature set, which is way cool. Uncool though, was the announcement that free public “pads” could no longer be created, and the entire service would be discontinued on March 31, 2010. After much uproar, Google and EtherPad revised their stance, promising to leave the site up and free to the public until the entirety of the source code (and the AppJet platform running it) could be opened to the public, allowing anyone to host his or her own Etherpad instance.
Though the process is still in the early stages, many are already setting up their own EtherPad instances, getting ready for the day Google pulls the plug. I’m among these hordes, and I’ll probably toss up an Ubuntu server walk-through once I get mine fully working at etherpad.jordanhollinger.com.