KitUp! had a cool story yesterday on MagGrips LLC which is a company that manufactures die cut grip kits for magazines and weapon systems (like the 30 round Magpul 2nd generation PMAG). The whole idea is to bring custom stippling to the recessed spaces on magazines (or on a weapon). Since, they are die cut they fit perfectly and offer a great look as well as grip.
Read all about it at kitup.military.com.