I thought I'd check out some of the good deals out there for you, so you can get your hands on some games if you haven't already. Please don't hesitate to post a comment here if you discover some other good deals out there.

GOG.com has the HoMM V bundle on sale for $20, that's a decent buy, especially considering you get the full game with all expansions, DRM free.
They also have a Might and Magic 6-pack Limited Edition available for $10 - that's a steal. What's good about this is that you get all the six first M&M titles compatible with new Windows OS. Also check out the bonus material.
If you're into point-and-click adventures, have a look at Dreamfall: The longest journey. Made by Funcom in Norway, it's actually quite a good game in its segment. Currently at $15 it's not on the cheapest side, but I think it's worth it.
That Master of Magic is available for $6 is a good note on which to end the GOG recommendations. If you see any other good deals there in the coming days, let us know; they're bound to update their sales list soon.

Amazon.com also have some good deals up; the Bioshock triple pack downloadable for $15 being one of them. These pages change all the time, and I also see the American and UK sites being hugely different, so I'd recommend browsing for good deals and see if anything piques your interest. Generally, Amazon will lower their prices on mid-range hardware slightly (since new, upgraded models are arriving in January), but most software aren't necessarily on sale just because it's New Year's.
One thing I noticed is that the Heroes VI complete edition is available for $10, so if any of you have been waiting for the price to drop on this game, now's the time. What's good about that is that the game comes ready-patched and with the expansion and the DLCs.

Steam's holiday sale ends January 3rd, and their objects change every day. They have "daily offers" and "lightning sales" (every 8 hours), and as I type this I can see the same Heroes VI Complete edition for sale at -75%
I also see some good deals on Age of Empires II HD, the indie game Legend of Dungeon and Metro: Last night. When you browse for games in this store, keep an eye out for games that are playable on multiple platforms; Windows, Apple iOS and Linux.