From the Site: Dino Run SE is a retro-styled, action-packed prehistoric racing game that can be played by yourself or with up to 3 other players in many different multiplayer levels. This new version is an update and expansion of the original web game.
Basically, Dino Run SE is a retro style platformer where you take on the role of a dinosaur trying to outrun the fiery apocalypse caused by the shockwave of a large meteor impact. The debris cloud is always just a few feet behind you... run like mad, catch a ride from a pterodactyl, eat up smaller creatures.. time your jumps to go from hilltop to hilltop.
Even though the website claims the offer is only good until Oct. 9th.. This finely tuned indie classic is actually available for free until Oct. 10th. So head over soon and grab a copy before this promotion expires. (Click Buy Now and enter Free for your price)
BTW: You also get the games soundtrack for free when you download the game.
You can also play the original web based flash game here to get an idea of the gameplay.