Easy to pick up and play, Amplitude is a must-have for gamers who love rhythm/music games. Local multiplayer and various difficulty settings make Amplitude excellent value for money, though a lack of online multiplayer or additional DLC hurts long-term longevity.
A fun RTS that doesn't take itself too seriously. Punishing campaign difficulty and online multiplayer modes help build a long lifespan for our barbarian friends. While it won't replace your Starcraft or Total War, it'll complement them nicely when you want a more lighthearted change of pace.
For fans of hardcore games such as Super Meat Boy or I Wanna Be The Guy, 10 Second Ninja X is a fantastic game. The short bursts of gameplay make 10SNX great for people with limited time, but the difficulty won't be for everyone; grab the demo first if you're new to hardcore platformers.
Fairy Fencer F: Advent Dark Force is a solid, fun JRPG experience with a strong anime flavor and many hours worth of content. If you're a fan of turn-based RPGs and pulling off stylish, over-the-top moves with finesse, this is a great game to look into.