These two currently tend to take most of the abuse over Winter.
Firstly a 1993-1995 (I'm not sure of the exact date) steel Saracen frame, powder coated and built up with the ever reliable Deore M510 groupset and v-brakes. Full mudguards and a rear rack (for thermos, pipe and slippers) push the weight up to about 34 pounds.
Then I have another eBay bargain frame purchase. This modern generic pile of crap was decaled up as a virtually unused 2005 Claud Butler Olympus XT. Top of the range bike for the year.
After a trip to the powder coaters and another Deore groupset, this time with discs, it anonymously performs it's winter duties with crushing mediocrity.
I know it's modern; but secretly I actually quite like it, and rarely feel to need to even clean it.
I'm also currently working on a 1993 Kona Lava Dome, and I've just been given a 1998 Saracen HardTrax frame to furnish with parts from the stockpile. Both will be built up more of less period correct for a bit more winter mud shunting.