Capturing your start-to-be with a wiki

Does anyone know of a good FOSS product that emulates the functionality of Lotus Teamroom? I am anal about my organization and much prefer a directory structure for it's ease of organization. I currently use a hacked verstion of Relay (http://www.ecosmear.com/relay) with a custom written XML parsing function to add context to directory and files for my Wiki-/teamroom- like functionality. However, is there a good alternative to this that a reader knows of?

I saw a big momentum improvement in my startup as soon as I got a development server setup with Trac. The wiki on there has definitely given us a place to toss ideas around and to have them recorded. The problem with email is that things get too spread out across different threads. The wiki lets you structure it more permanently.

OR just start a blog....