If you happen to like BFG then this is the best sale I can remember them having. It is half off their normal game club member prices (which are 30% of their regular prices, so that makes them 65% off regular prices) for all of their games. Standard edition games are all $3.49 and Collectors Edition games versions are $6.99. This is available to everyone.
You do have to use a coupon code, but those are listed in the announcement on their website and again on a large banner at the top of their website.