Why garage floor paint ideas are flawed:
Water based and oil based paints are simply not designed to put up with automotive traffic. They are also not designed to adhere to smooth concrete that has not been properly prepared. Paint is generally very thin, lacks chemical resistance, abrasion resistance and UV resistance. All of these issues are a daily occurrence in the garage and play a major role in the determination that painting the garage floor is simply a bade idea.
Why coating a garage floor is a better idea
If you want a system that will stand out, TrueLock makes a metallic garage floor epoxy stystem that will leave your friends drooling and your wife thoroughly impressed. Rust Bullet has a series of top coats to add color. Paint chips are also used in Rust Bullet and epoxy products for additional design options.
One additional option to consider is a high gloss penetrating sealer such as TLPPC. This product penetrates like a traditional sealer, but the urethane component leavea a fun shine like not other paint or coating product will.