Hello,
Just wanted to share this with the community. iRobot, here in Massachusetts, has a hack page,Create 2 Projects, that looks really fun and has lots of different projects associated with the Roomba. Although the startup kit is expensive, I would imagine the projects could be performed on a used Roomba if available. Raspberry PI's, Arduino's, and 3D printing are all involved as well as neat simple mods. Sounds like something Ben Heck could do as a "follow along with Ben" concept. Just a thought but definitely a neat use of the Roomba.
Thanks for reading.
Vince
ps. not affiliated with iRobot although I am looking at their career section.