I got one of these Osiris wallet tools from a rep when i worked in the local skateshop.. works a treat for a mid sesh tighten up when a bolt starts rattling, however i would never even consider changing a board with it.
fits in my wallet, has the 3 ratchets u need, a bottle opener and a little hole that an alen key fits in perfect.. this is by far the best thing Osiris have ever done