This looks sweet and really makes me wonder about switching to Mac Mail. Being able to tag your email with actions would be a great addition for GTD workflow.
Open Thread: Mac Mind Mapping, and how you use it | 43 Folders
This is a great article out of 43 Folders. I’ve been using a variety of Mind-mapping tools and really enjoy Vue (http://vue.tccs.tufts.edu/). Considering it is both free and has a good range of basic capabilities, it might be the best entry-level mind-mapping software available.