Figured I'd start a thread locally on what weights I've found on various parts that were on their way off the car. Please add your findings as well....

Stock exhaust system w/o chrome tips: 49.5 lbs

(I rented a SawzAll from Home Depot and hacked up my old exhaust in the spirit of R&D...)

Left Muffler: 18.0 lbs
Right Muffler + "Y" section and piping leading up to resonator: 22 lbs
Resonator/Mini-muffler, piping, Helmholtz tube and flange to where the cat is: 9.5 lbs

FWIW the Resonator / Mini-muffler is straight through similar to a Magnaflow.

Catalytic converter: 13 lbs
Test pipe + Secondary O2 simulator: 4 lbs (including flanges)

Factory flywheel: 14.5 lbs
Comptech flywheel: 9.5 lbs

When corner weighted at Autoscope, the car (with turbo & I/C) weighed 2740 with a half tank of gas, floormats in it, Ultimate Racing 2.5" exhaust, but JB speaker box (21 lbs) and spare tire/jack removed.