Since everyone is listing stuff I'll go ahead and do it too.
1st dual exhaust system - $110
2nd exhaust system - $100
3rd exhaust system - free(kind of...was done when my swap was getting done)
Intake on 7A-FE - $80
CAI on 4A-GE - $60
Engine Swap(engine, tranny, ECU, labor, replacement parts, performance parts, etc.) - $3,000
Coilovers(eBay) - $100
Eibach Springs - $200
KYB GR-2 Struts/shocks - $200
Suspension Tech Sway Bars - $230
TRD Quickshifter - $120
1st alarm/door locks - $75
2nd alarm/remote-start - $65
Power window kit - $130
New door panels - $100
Volt Gauge - $40
Audio Stuff - $1,500(lots of different stuff over the years)
Paint Job - $1,600(if you count insurance money, otherwise $600)
17" Wheels/Tires - $820
18" Wheels/Tires - $100
2 new 215/40/17 Tires - $220
New Front Bumper - $75
New Driver's Side Low Beam Headlight - $150(back when I was dumb...purchased from dealer)
New Passenger's Side Low Beam Headlight - $75(still don't have it yet though. >

>)
Bulbs, Neon Lights, Switches, Wiring, Relays, etc. - $100
Clear Corners - $30
Clear Sidemarkers - $50
There's some stuff...I know there's a lot more that I'm forgetting, and tons of supplies for custom stuff(paint, fiberglass, wood, etc.) But you kind of get the idea...