Good bass amp for both bass & guitar?


So I own both  a guitar and bass, yet I only have a guitar amp (Marshall AVT100.... meh heh)

I am in the market for a new tube guitar amp, but I've also read that playing through a bass amp can actually give off a better sound (depends on the ears I guess)

Do any of you do this? Are there any bass amps you can name off the top of your head for me to take a look at?

I would definately want tubes in it :p

Fender Bassman or DualShowman, Fender 75 in 1x15 combo or head; Ampeg B15 was great, probably pretty hard to find one these days, in terms of what you can find more late model, can't beat the '59 Bassman 4x10 combo reissue
Traynor's tube bass offerings back in the day are pretty sweet, too.
Buy the Fender Showman here in the classifieds.  Just trust me......  Leap of faith... with a nice 2x12 bottom it will do wonders for both, if bass only get 2x15 GUITAR speakers, add horn if needed.
Well I use a 600 watt Carvin bass amp for my guitar needs, BUT The Orange Thunderverb 200 is designed for both. And it's wicked