There are some rubberized tile products for concrete floors that are not terribly expensive. They interlock, and you just lay them down and trim the edges.
I'm thinking about eventually laying a brick floor over the uneven concrete in my garage. I would have to adjust the door height but the man door is already high enough that it would actually match once the bricks were install. My garage has a 10 foot ceiling so I wouldn't miss the space. I've paved smaller areas with brick and it is pretty easy to get good results. It looks great, too. You don't need to bed brick pavers in mortar, if you provide a good stable base you can sweep fine grade sand in between the bricks to lock them together once they are laid.
