Free mods:
Reset computer
Remove intake air restrictor
Google will tell you how to do these...
Also, if you are looking for things to do why not try some preventitive maintenance? All the below stuff is cheap...
You could:
Change tranny fluid
Change diff fluid
Change plugs
Change oil
Set air pressure in all tires perfectly
Clean MAF, IAC, PCV pipe
Replace PCV valve
Bleed brakes
Put some Sylvania Silverstars or PIAA headlight in
Detail car until it shines like the sun