From GoG.com: The Double Insomnia Promo will feature more games than ever, and two simultaneous pools: Seasoned classics and Fresh new titles. If you know how this works you're probably trembling with anticipation already (or is it fear?), but if you're just joining us… well, you'll still probably make it out okay.
What's all the hullabaloo about? All sales are offered in limited quantities, and the number of copies remaining is labeled with a huge counter on the front page. There are two pools, and only one game from either pool can be on sale at one time. Once a game sells out, another will immediately take its place so that two are always available. If you missed your chance, fear not but keep your eyes open! Your favorite one will probably be back. Insomnia mercilessly goes on, day and night, until every single unit is gone - like a carousel of deals. You might even have a chance to get a free game, if you're lucky that is.
current deal has Indiana Jones and the Fate of Atlantis for $3.79