Our system is similar to Bouncy Bouncy's - we have 4 bikes hung on rubberized covered hooks that hang from the ceiling in the garage. Just one hook per bike on the ceiling and the rest of the bike just rests against the wall.

Of course, we have more than 4 bikes, so the rest of the bikes are in our storage area under our house resting up against boxes and all the other stuff that is in storage, you know, like christmas ornaments, barbeque grills, etc.