1 amp, 1 guitar, but multiple "rigs" now. :D
My guitar, is a bc rich mockingbird special in white, with a bareknuckle warpig in the bridge.
For Rock, hardrock and metal, i run a maxon od808 into my marshall 6100lm, and tame the fizz and boost low mids with an mxr 10 band in the loop. Gets it sounding super thick. I do this on both the crunch and lead channels.
If i want to play more classic Cream sort of stuff, i just go straight in, or sometimes boosted into my crunch channel.
For doom, i run straight into the clean channel with either my Bluebeard fuzz, or my boss fz-2. On occasion i will use the fz-2 as a boost on a low gain crunch channel to get a more raunchy tone, or boost my bluebeard with my maxon to give it more edge.
Thats pretty much it for the most part. Gets me a wide range of tones :)