Renegade Studios offers a free print and play version of its Wonderland Card game.
Good Little Hunters is a free print and play card game where players guide their pack of animals to survival. It involves simultaneous action selection, bluffing and deduction.
Pairs is a free print-and-play game from Cheapass Games. You can also purchase printed editions of the game at the same site. From the publisher’s description:
The Pairs deck contains only the numbers 1 through 10, in a triangular distribution (1×1, 2×2, 3×3, and so on up to 10×10). The basic goal of Pairsis to avoid getting a pair. Your odds will depend on what cards you hold, and which cards you have seen! Scoring pairs earns you points, and the first player to reach a target score is the loser.
Minute Diktator is a free print and play game in which two players vie to get the support of the “Council of Five” to replace the departed Dear Leader.