Just discovered this; if you ever enjoyed Sonic 1 / 2 / 3 / +Knuckles on the Megadrive / Genesis then you need to have a look at this: http://www.kickstarter.com/projects/galaxytrail/freedom-planet-high-speed-platform-game
It's very true to the style and a very good demo worth playing. You can pledge $10 to get the full game once released. Have fun!