The Ouya is an Android-based microconsole, famous for proving that a record-breaking Kickstarter campaign does not necessarily mean a commercial success, or even a good product. Despite the initial hype, it was too weak even for the time, the hardware had a number of issues, and it even had a botched launch, with backers only receiving their units well after it was in stores.
And yet, since it was dead-easy to port from Android (in fact you can just install most Android .apks), it quickly amassed a library of well over a thousand titles — mostly mobile games, sure, but also media players and emulators for several classic systems (most up to PS1 run well, but N64 is very hit-and-miss). For a $99 machine, it was not a terrible deal. Then again, it was not a fantastic deal either, so it didn't take off. The company was acquired by Razer in 2015, and the console was discontinued.
Is it worth getting one now? No, it's quite outdated, and plenty other devices can do the same things better. But if you happen to bump into one dirt cheap in some clearance or garage sale, you can still squeeze some use out of it. You can grab its games from the Internet Archive. You can even install a somewhat newer version of Android on it, check the XDA Developers forum for more on that.
An Amiga classic, one of the most brutally hardcore games ever. An accident teleports a scientist to a world where everything is out to kill him.
Beast Boxing Turbo
Fighting
It's like Punch-Out!, but with monsters.
Chronoblade
Beat 'em up
A brawler with RPG elements, from the creator of Lemmings and GTA.
Duck Game
Action/ Platformer/ Party
A quirky fast-paced multiplayer 2D versus platformer with ducks and guns, lots of guns.
Final Fantasy III
RPG
Updated remake of the Famicom classic (not to be mistaken for the SNES game that is actually Final Fantasy VI).
Flashout 3D
Racing
Futuristic racing/shooting a la Wipeout.
Giana Sisters
Platformer
A damn good old school platformer, sequel to a classic European rule-63'ed Mario clone.
Maldita Castilla
Platformer
Spanish homage to the Ghosts 'n Goblins series. So deliciously old-school, you could easily believe it's a late 1980s arcade under emulation (and the music was actually produced by emulating the YM2203 sound chip, which many arcade boards used back then).
Order & Chaos Online
MMORPG
Gameloft's generic WoW. Quite impressive for the system.
Ravensword Shadowlands
Action-RPG
Very reminescent of Elder Scrolls and Fable.
Saturday Morning RPG
RPG
A comedy/nostalgia RPG inspired by 1980s cartoons and pop culture, with music by Vince DiCola (Transformers, Rocky IV).
Shadowgun
TPS
A very badass sci-fi third person shooter clearly inspired by Gears of War.
Sine Mora
Shooter
Beautiful shmup with time-manipulation elements and character designs bound to please the furfags.
Sonic the Hedgehog 4
Platformer
Does this even need much of a description? It's Sonic, it's 2D, it's good. Both episodes are available, as well as Sonic CD.
Towerfall
Platformer
You and three other archers shoot arrows at each other in this fast paced multiplayer platformer, also has a 1-2 player campaign, tons of fun.
Vendetta Online
MMORPG
A mix of online RPG and space simulator. Similar to EVE, but more streamlined and action-oriented.
Void Pyramid
RPG
In a distant dystopian future you have been convicted for a crime you did not commit and are sentenced to death in the Void Pyramid: a literal pyramid floating in space, filled with monsters and traps. This RPG is dripping in 80's charm with a very easy to learn system. It's only a few hours long, but that's because it's made to be speed run. How fast can you escape?