So, I've got a Hughes & Kettner Edition Blue 60 amp, which is the finest solid state amp I've ever heard (unfortunately not a tube amp), with beautiful cleans on my Fender MIA Stratocaster.

I want to achieve a nice bluesy sound, but with the built in distortion (sucks big time) and with my Zoom G2.1u I just simply can't do that.
So, which pedal would you recommend for that light bluesy distortion/overdrive (kind of SRV, Clapton, John Mayer <- I love his tone
I was thinking on Boss Blues Driver, Digitech Bad Monkey, Marshall BB-1 or BB-2, or something else.

Of course I won't be able to achieve their warm tone 100% perfectly because of the lack of tubes, but I just really want a bluesy tone that's fun to play on.

Also, I'm a bit broke (because of the guitar, but it was worth), my budget is about 100 $, so don't recommend me to buy a tube amp, sometime in the future I definietly will buy one.
I'd say the Boss Blues Driver, but it sounds better with humbuckers. Try one out with a Strat and see what you think. Other than that, a Tubescreamer is the obvious choice.
Plus, he'll be able to use a Tubescreamer with whatever amp he gets down the road. For now, it'll work fine with his amp.
^ Mayer certainly uses the above pedal in his current setup (though he is a gear *****). I should be getting my tube amp soon so that will be my next purchase.
Well SRV used a Tubescreamer, so that will give you that mid 'hunp' that tubescreamers give. But for a tight budget i suggest a Boss SD-1, my favourite Boss pedal