Since there's a lot of confusion about the MegaSquirt I thought I'd link everybody to a great FAQ page from DIYAutotune:
http://www.diyautotune.com/faq/faq.htm
It really hits all the main points I think. I've almost got my MS'd car drivable so I'll post up a full review and rundown of what parts I used and the cost in a few weeks. So far I couldn't be more happy, the only down side (if you see it that way) is the amount of reading the MS requires. You really are commiting to an education in EFI when you jump into the world of MegaSquirt? But, you know what they say, if you want it done right, do it yourself!
Fred
Instrument Cluster and Speedometer Repair