Oxford University Press is in the midst of a winter sale. That means you can buy the Oxford Latin Dictionary for $125. The library edition of R.B. Bernstein’s well-regarded Jefferson: The Revolution of Ideas is going for $12.
Some of the bargains aren’t much better than what you can get from a little hunting around Alibris or Abebooks, but I’ve never seen a better price for the OLD. Every serious student of Latin ought to have one — as should anyone thinking of studying the language in the future.
Edit: The Jefferson book is not the one I thought it was, Bernstein’s short Jefferson bio from a year or two back. It’s actually a life of Jefferson for junior-high students. Probably quite a good thing in its own right, but disregard my endorsement above.