If you're holding out on starting the Mass Effect series until everybody can be happy with the conclusion and haven't picked up the first two titles yet, Amazon is your Shepard. They're offering digital downloads of Mass Effect and Mass Effect 2 on PC for $6 each this week. If you'd rather have the Digital Deluxe version, that's just another two smackers. I played the series on Xbox 360 but I've been doing a lot more PC gaming lately and I just can't resist a cheap game, so I'll probably wind up grabbing these.
Also, if you haven't picked up Batman Arkham City and were going to do so for PS3 or Xbox 360, that's on sale this week for $39.99. Just a heads-up.