Erik over at Tenkar's Tavern, for the rest of today there will be a huge number of blogs posting about the Dungeons & Dragons retro-clone Swords & Wizardry. A full blogroll of the participants can be found at 2,000 Coppers, though I don't know how long that list will be up.
A product of Frog God Games, S&W comes in three different varieties, each in increasing complexity: the White Box Edition, the Core Rules, and the Complete Rules. The latter of these is also the basis for the recently-revealed and highly useful SRD.
Though there are many similarities to be among all the various retro-clones, Swords & Wizardry has a few tweaks that I especially appreciate. Firstly is the support for both ascending and descending Armor Class - I get that the descending system was the original and most people who actually play are used to it, but as a newcomer I find the latter easier to grasp.
Another interesting thing about Swords & Wizardry is the way that, for character building, Race is semi-detached from Class. I say semi-detached, for while S&W offers a bit more flexibility than the traditional Race-as-Class systems, it's still not quite at the level of later editions that allow any given combination, no matter how wacky. Of course, that's just how the rules are written, and with a bit of creativity it's perfectly possible for a player or Referee to account for any combination their heart desires - indeed, Swords & Wizardry make it easier to do than many other retro-clones.
Anyway, as a way of encouraging folks to check the system out there's a couple of coupon codes for 25% off Swords & Wizardry products out there, for use today only - for Frog God Games the code is SWApprDay, while for the SRD Store it's SWAD252013. There's lots of products beyond the basic rulebooks available at the reduced rate at both sites, so if there's something Swords & Wizardry-related you've been waiting for, today's the day to pick it up. Also, again, there's over a hundred different blogs discussing Swords & Wizardry today, and you can read all of them from over at 2000 Coppers.