First things first. I consider Jeff Talanian a friend. I've covered his booth at Total Con and other conventions when Jeff had to scoot for a few minutes. On a gaming level, Hyperborea is one of the best OSR systems out there, and probably the one with the most options without overwhelming the players. Aside from that, Jeff is simply good people.
For the month of May, DTRPG is running a Dungeons & Dragons Sale, with included PDFs being offered at a 20% to 40% discount.
The entire Hyperboria Collection of releases is included in this sale, with the latest edition of the Hyperborea rules being offered at a 20% discount (9.60 each for the Player's and Referee's Manuals), and the various Hyperborea Adventures being offered at a 40% discount (6 bucks each). It should be noted that Hyperborea Adventures can easily be run with the OSR ruleset of your choice.
My personal favorite is Rats in the Walls and Other Perils. Heck, I even own the shirt!
You can catch the daily Tavern Chat podcast on YouTube - Tenkar