Thank you! I tried the paper wallet decryption for each key. It looks like they weren't BTC, LTC, or Doge unfortunately. Probably something I've long since forgotten about, or addresses I never actually used. I guess the mystery will be why I ever thought to save them in the first place.

I found what I think are two private keys I hid long ago (a pair of 64 character hex strings), which is great... except I have no idea what coin they would have been for. The only clue I have is that I saved them in early February 2014. I tried importing each one into a Dogecoin wallet (went to console and typed importprivkey "bunch of letters and numbers") and it didn't work so it either isn't Doge or I used the wrong syntax.

Around that time I was trying all sorts of random mining pools, shady exchanges, and stupid coins, so it could even belong to some trashcoin that doesn't exist anymore. Is there anything I can try beyond downloading wallets that sound familiar and attempting to import the keys into each one?