Open Source FDD tool

If anybody has ideas, statements, issues about past tools that they would like added, removed modified etc. please add to this thread, and i will try to synthesise a general requirements document for people to view.

I hope to use a hybrid development methodology between what i will call "open source" and FDD (i.e. feature sets or even major feature sets per revision or something, I haven't finalised anything).

I'm mostly interested in hearing what are the shortcomings and positives out of in-house tools currently used (come on guys pass the knowledge on ;D) and desires of those wanting a tool for their own projects.

If you would like to email me: