Aside from a CAI and some eye candy, not much. It is mostly show. 
I'd give you a pic of mine but ~ Don't have any saved anywhere. I'm the same as you ~~ Just for show, but in all Silver. No supercharger or turbo. Just CAI, exhaust, grounding kit, spark plug set, and coil overs. Nothing much. When I first bought the car.......when it was all stock, I took it out at 3AM for a test drive. Was a little curious. I had to slow down at 135 has I had no more road. This was 4 years ago. With the little wrench time that I put in ~ I've had it up to 152. There's a brand new Dyno shop where I live ~ Thinking about syncing everything together. Also, two days ago, while on my way to work......I raced an older Eclipse. He was quite, no exhaust, no bobdy work, and no turbo ~~ or so I thought......
......Long story short, I beat him. From a red-light stop, from a 30-rolling, and from a 45-rolling. Beat him. I don't tell you this to brag ~~ I'm 28 years old, there's no need for that in my life. I tell you this in shock! Truth be told, I didn't think I'd ever beat this guy. Maybe he was new. Maybe he was missing gears, or maybe his turbo just sucked (no pun in tended).
Who knows. What I do know is that I'm very thankful for everyone's advice on here. I stayed up late last night and read all of the links you all provided me. I'll let my clients know what I now know......
Message Edited by New2This on 07-04-2007 06:18 AM