MegaSquirt on a slant six. Most expensive part was the custom machined manifold and fuel rail - $600. All told, I spent around $1500 on the EFI components. I don't have any pictures of the first completed installation - right now it's apart for a bigger turbo.
Note that I ended up flipping the throttle body around between the times these two pictures were taken. It's a Ford Crown Victoria throttle body on a piece of aluminum water pipe from McMaster-Carr. They didn't have Edlebrock's cast elbow adapters when I put this together; getting that part fabricated was about as expensive as buying a ready made Edelbrock piece is now, as I can't weld aluminum.