I essentially renovated my garage for winter use this year, and among other things I used the Rustoleum epoxy from Home Depot. It's a single car garage, so only 250sq/ft and it was *just* enough. So far, it's been extremely durable and I'm very pleased with it. If you're still working on bare concrete you should do yourself a favor and epoxy it.
The benefit of not staining the floor with every spill is obvious, but it also brightens up the garage significantly. The color of what I used is a light beige color, which reflects the light a lot better than oil-stained and pitted concrete. Here is a before and after pic, representing nearly a week straight of work:
