Writing Tools... So close: Ooh, Missed!

I'm always looking out for a good tool to help in writing or mapping ideas. MindJet's MindManager is brilliant, if expensive for individuals, and not available on-line. PBWiki makes great tools for sharing ideas on-line. Google is helping me move a lot of my writing to the web by letting me move documents onto a universal desktop space. (To say nothing of Google Search itself, but I'm a bit biased towards that company.)

I'm hunting for the perfect -- or at least, usable -- idea mapping software. An acquaintance suggested Wridea. I checked it out and, sadly, have to say it takes writers back a notch in terms of usability. The fact that the software is affiliated with a mail list management company (read all those wonderful e-mails you don't want to receive) makes me leery of their motives in getting e-mail addresses from users and those with whom they share their idea maps. (Sorry, guys: smoke, fire, and all that jazz.)

If anyone has a better site for idea or story mapping, please let me know: comments always read.