While driving on the interstate at 55 MPH I suddenly lost power without braking. I eventually had my foot all the way down on the accelerator and was still losing speed *TRYING TO GET OFF*. I coasted off the interstate and then parked it. I tried to move but it would not go anywhere in "D". I assumed a brake cylinder locked up and was slowing me down but I did not skid the tires. Perhaps a wheel bearing?
Also, the engine was running just fine the entire time.

Now for the weird part:
I get it towed home and then today I go start it, put it in drive and suddenly its like nothing ever happened BUT the brakes do feel kind of like they did when the master cylinder went out 2 months ago. Oh and I flushed all the break fluid out then, but now I see its BLACK again!

Any ideas?