I've printed my game and used Franklin Gothic Medium. A common irk (not quite a complaint) among a lot of playtesters was the legibility of the cards.
What would be a simple, free font to use? I wanted to use MPlantin like the older magic cards or Optimus Princeps (which I believe is a rip-off of Trajan Pro, used by Dominion). Both of those seem sketchy. I've been up and down font squirrel with not much luck. I didn't realize how difficult it was to choose a font.
I tried every one of everyone's suggestions, then did a few searches on legibility. Arial Narrow seemed a bit too squished for my taste. I ran them by my brother (since he is always near as an objective observer). Libre Baskerville (which is close to MPlantin) won out, followed by Tahoma, then Verdana, and finally Arvo. I really appreciate everyone's input! It really helped drive home the decisions.