Comp cams pro plasma nitriding
Cryo is great for wear parts like pistons, crankshafts, connecting rods, transmission gears and synchros. It works on a lot of other stuff too.
A lot of people are using it for street racing and track days or just general enthusiasts. Plus, its a relatively cheap process. The one thing you have to remember is cryogenic treatment is a full-bodied process rather than just a surface coating.
Take a look here...
http://www.nitrofreeze.com/racing.html