A photographer friend of mine uses the FatMax 4-in-1 Mobile Work Station, and I could not wait to get one and try it out. What I like, is that it easily unfolds, and there is all the stuff you are constantly needing on set, like C-47's (clothespin), grip heads, mafers, make-up kit etc.
My only concern is how well it will hold up on-set. The metal and construction seem a bit flimsy. We shall see.
This can be found at most big-box retail stores like Home Depot and Menards, or you can find it at Amazon.