This was my entry to the ROBOMO '06 line follower comp. It is a Microbot brand kit that uses an Atmel micro and 3 sets of IR leds to track the line. It did ok after A LOT of tweaking to make it work correctly.

I built this literally at the event and programmed it with my code to correct some issues it had. It didn't finish last, which was like First to me under the circumstances.
This is the (new) Rump Shaker.
Its a microbotics kit using BEAM technology to follow a line. I gave this bot to a Robomo member who had never built a robot before.
This is my newest line follower, Growler.
It is also a Microbotics brand kit, that uses the ever popular Atmel mega-8 micro with a '293 motorcontroller.
While not the fastest line follower I've ever seen, I have been able to get it to 50 cm/S.

Which I feel is pretty darn good for being a cheap kit robot.
This is my Flocode line follower. Its a reasonably fast kit available online. And works very accurately for only having 2 line sensors.