I finally got some mods going on this thing, albeit nothing serious just yet. It still hauls ass and will outrun alot of newer cars. I really love beating ricers when I feel froggy, and the look on their faces when they get beaten by a "family sedan" is priceless...
Performance mods:
-CE stainless steel 2.5" y-pipe
-Place Racing style cold air induction w/ K&N conical filter
-Stainless steel braided clutch line
-Stainless steel braided brake lines
-Brembo slotted & zinc coated brake rotors
-Optima Redtop battery for a strong electrical system foundation
-Mobil 1 synthetic motor oil every time
-New 300zx fuel-filter
-NGK V-Power spark-plugs
-New Knock-sensor
-Cleaned throttlebody/new gasket/adjusted throttle cable
-Cleaned IAC valve & adjusted idle speed
-Cleaed misc. EGR crap I could get to and emissions stuff...
-5th gen Maxima clutch upgrade
A crappy pic of the brake setup before I undercoated my wheelwells...

The y-pipe was undoubtedly the best $150 I could have spent on this car performance wise. It gave the car a nice performance boost throughout the rpm range, but it was most pronouncd in the higher revs, where the VQ needs some help to start with. The car does sound sorta weird now though, but that should be fixed as soon as I get the better cat-back system.
I did just make one MAJOR upgrade also: Brembo slotted brake rotors-front & rear, Carbon/Ceramic brake pads and stainless-steel braided brake lines. This made a gigantic improvement in brake-pedal feel and gave me a pretty decent reduction in stopping distance and brake fade is significantly reduced also. The Brembo rotors are zinc plated so they will look good for a long time and stand out well unlike old, rusty stock ones. The calipers were painted red when I got the car, but I think I am going to powdercoat them either silver or black.
When I got the car it idled kinda low and the lights cut out bad when the bass hit. Cleaning battery connections and the Red top helped the lights, and after taking off the throttlebody and IAC valve and cleaning them it idles perfect and is a little more responsive.
Upcoming Mods:
-Greddy SP2 catback
-00VI-variable intake manifold
-Emanage Ultimate(tuning)
-Powdercoating brake calipers(don't like the red)
-Turbo kit :)