I used an epoxy paint I bought at Home Depot for my garage floor. I learned a lot about floor coatings from the following website:
http://www.epoxyproducts.com/garage4u.html
I ended up using Behr products epoxy floor coatings, and decided against using sand or other traction aid in the mix, after reading the above article which basically said anything you add to aid in traction will reduce the lifespan of the coating and contribute to hot-tire pickup.
Prep was 90% of making the paint work well. I cleaned the floor with special concrete cleaner (also by Behr), and used a couple of very stiff acid brushes and a pressure washer to make sure everything was grease and contaminant free. There were a couple of spots on the garage floor where my Buick leaked, and I spent a lot of time making sure they were cleaned up before primering, then painting.
Even though the product says it does not need primering, I opted to prime it as my garage floor is old, and I was concerned about efflorescence in the concrete, as well as to seal a couple of small cracks, etc...
Attached are two JPG's (hope ya can see them, I've never used the attachment option before..) of my floor, 7 months after putting the paint on. It looks nice, and cleans up very easily with a hose, and degreaser, etc.. I'm happy with it, and I have had no problems with the stuff coming off. It cost like $22 a gallon, and I had plenty left after I finished off my garage floor. My parents liked it so much, they want me to do their garage floor too.
Billy
Montgomery Village, MD