roWiki, a php wiki that uses only text files
twisted, a python base asynchronus networking framework:
Glade asks for users and beta testers:
Glade-3 is not much far from being usable, but unfortunately at the moment the developement is not as fast paced as we would like. Given that the Glade user base is mostly made of developers it would be great if you could help with it: work on Glade-3 may be a great learning experience since the difficulty of things you can work on range from basic GTK+ GUI programming to the deep secrets of the GObject system.