help with shirt ideas

I am having some shirts made for my shop to give away with our logo and our body shops logo but i want to have a few diffrent ideas for the front. i was thinking of "got air?" with a bag or maybe the outline of a slamed truck? I want the front to be 1 color so letters and an outline or something what do you all think? the idea is to make a cool shirt people will wear to help get our name out.Thanks in advance