Hondata is a company that offers an ECU reflash and a ECU piggyback.
I.E you can get your ECU (Electronic Control Unit - or the brains of the car) reflashed so you have a higher redline, VTEC engages earlier, and you harness more power (even more power with other mods).
If you're a tuner you'll get their ECU so you can tune the car and get better gains.
Lastly, there is the Hondata IMG, and IMG stands for Intake Manifold Gasket, cheap and it yields OK gains.
www.hondata.com
www.clubrsx.com - forums - ECU tuning