Here we have some 1971 Topps Coins I got for super cheap a while back. I'm still waiting for Topps to put out a new set. The last time Topps put out a coin set was in 1990. Actually they put out 4 sets in a row from 1987 to 1990. I bought a few packs back then. There kinda silly but they are different.
According to the Standard Catalog these coins had 3 types of backs, 1-50 had brass backs, 50-100 had silver backs, and 101-158 had blue backs. You can see the difference in the backs here. According to the Catalog these are worth about 2 bucks a piece in mint. These are not mint. I think I picked all three up for under a dollar.
Topps also put out a coin set in 1964, which has some huge names in it. Not that the 71 set doesn't.
Back in 2003 Topps Gallery had cards that had money embedded. While I don't think we need another set of Topps coins. Personally I think their a little awkward. But I think Topps could come up with a hybrid card maybe with a Topps coin embedded in the card. They could have parallels like most of the other stuff, even buybacks. Well it's just an idea. Oh maybe even 24kt gold coin cards. If they can make 24kt gold cards I'm sure Topps could mint a 24kt gold Topps coin. That would make an interesting 1/1 card.