I just flashed my Visiontek GeForce2 GTS($140) to an Elsa Gloria III ($600) card.
Also did the resistor mod to change the card from GeForce2 GTS to Quadro2 PRO.
Awesome. Kinda like an OEM Gloria III for $140.
Flashing at the very least, allows you to use that manufacturers drivers.
I can't agree more with your statement:
""It's boring when everything works, it makes you want to do strange things that are likely to cause serious damage!""
Trouble is, it still stays boring, because after every change it actually still works. Almost makes me want to put mt old 3dfx V3 back in, just to keep me busy fixing stuff.