There are hardly any baseball cards I'm willing to spent more than $10 for, but I made an exception in this case. It's the single most money I've ever spent on a single card. And of course, it is Mike Schmidt.
1999 SP Signature Autograph
I paid $46 for this back in November 1999. More even than I paid for his rookie card. It's the only Schmidt auto I have and I'm very happy with it. Earlier in the year I had paid $6 for the non-autographed version.