oh yikes, completely missed your follow-up reply – sorry about that! I have a giant bulletin board and notecards. I throw each idea on a notecard and see if it fits into a category (methodology, etc) So far there’s lots of loose cards floating around.
Other than mind-mapping, I haven’t found a good/easy way to display it and allowing comments/input. Sometimes the high-tech versions take a lot of fiddling, and can be hard to update which frustrates me. I will keep searching though. I’m sure there’s a good solution out there somewhere 🙂