That's funny. I actually heard about this cease & desist situation on the news awhile back but had forgotten about it. Fortunately, I don't exactly think I'm on "Monster's radar" since I'm a 5 gal at a time home-brewer living abroad in Japan.
I'll check into the Mountain Dew beer idea--the flavors are at least similar. I'd be worried about using a "Dr Pepper Beer" recipe because it is so wildly different in flavor.
Thanks for the comments. I'm not sure if I'll get around to actually attempting the project but I appreciate feedback on the idea in its infancy.