its simliar yet vastly better than Freelancer. (I played it before it went retail (beta) where it was still free)
It's similar in that it's in space, has battles and trading. That's it. EVE is more of a spreadsheet with some fancy UI, while Freelancer is more of a FPS in a 3D battlefield with some trading thrown in.
EVE is "LOL I HAVE +5 POINTS IN GULLOTINE FRIGATE WEAPONRY, I WIN"
Freelancer is "LOL I HAVE A HEAVY FIGHTER WITH NANOBOTS AND I CAN ACTUALLY FLY, I WIN"