I don't know how I missed your (long ago) message about mobile devices, but I do a lot in this area. (See www.k12handhelds.com). In the past, we have done a lot with handhelds -- now that this technology is going out of vogue, we are focusing on the new sub-$300 mini-laptops and cell phones. In terms of tools, I prefer open source web-based tools like Moodle, wikis, blogs, etc. If you'd like to chat more about this, drop me a note at karen AT k12handhelds DOT com.