In the sidebar are some handy guides to M.U.S.C.L.E. collecting, from figure classifications to cleaning techniques. If you are serious about collecting M.U.S.C.L.E. figures and accessories you should find these guides extremely useful as they can help you catalog and take care of your collection as it grows.
Also be sure to check out the blue links! These are fantastic external resources into M.U.S.C.L.E. collecting and its history, accumulated by various M.U.S.C.L.E. enthusiasts which has taken years to research. The knowledge the authors of these sites have contributed to the hobby is invaluable.