I have gotten so much water in the brake system of one car that it freezes in the AM and that first pedal push yields nothing until I really press hard (no, it's not the vac assist screwing up).

Anyway, what's the best way to flush all 4 calipers?  I could do it the old fashioned way with my wife on the pedal and do each wheel, but I know there are some nifty air operated devices out there, and I think I've seen a device that you kind of pump with your hand, sort of like a vacuum pump.

Either get a mighty-vac or speed bleeders.  A mighty-vac will suck out the fluid.  The speed bleeders are just like the nipples on your calipers but they have a spring loaded ball bearing that when you open them doesn't allow air back in.  Therefore you could attach the hose to the nipple, open it and pump the brakes yourself without having to open and close the nipple over and over.  I use them on my bike, and even though the brake lever is within reach it's much easier.  I think they sell the mighty-vacs at walmart but the bleeders might be at auto part stores or online only.

I have a device that clamps over the MC and I can hook an air hose up to it and put about 3 PSI on it and push all the fluid out.

I got a compressed air powered fluid vac and I first suck all the old fluid out of the reservoir and fill it with fresh fluid.
Next I get a flare nut wrench and attach the vacuum to the bleeder valve and suck out the old fluid.
KEEP A EYE ON THE LEVEL IN THE RESERVOIR AS YOU ARE BLEEDING THE SYSTEM!
I change the fluid in all the cars about every 3 years

I do it the old fashion way, attach vinyl tubing to the bleeder nipple, insert end of tube into a soda can, open the valve, have someone step on the brake pedal and hold it down, then you tighten the bleeder valve...until clear.  Start with the brake piston that's furthest away from the brake reservoir

Quoted: I have a device that clamps over the MC and I can hook an air hose up to it and put about 3 PSI on it and push all the fluid out.

That's what I was thinking of.  What do you do when the reservoir approaches, empty though - run around to each bleeder screw and tighten it?  Seems like by the time I hooked that device up and babysat it, I could just call the wife over.  

I'll take a look at what my local auto parts emporium has though.