I have a 2004 M3 GT MT and have noticed for a week or so when i press the accelerator the engine revs but there is little power to the wheels. the other day i was driving in 4th and i lost all power to the wheels, i heard no noise, just lots of revs and no acceleration. I can put it into every gear even reverse and there is nothing.

 

180,000 k

 

#1 - sounds like a toasted clutch, but it shoyld have come on gradually.
#2 - when you say you put it into every gear and nothing - are you sure it's getting into gear at all? does the shifter feel normal?
#3 - bad synchros / worn gear teeth can cause it to fall out of gear, though you can usually hold the shifter to keep it in gear?
for #2 & 3 - Could be a sloppy shift linkage(s)

#4 - does it work when cold & die when it heats up, or absolutely nothing? added heat could boil water in the clutch slave and disengage the clutch on its own... theoretically that is.

Test it with the engine off, see if you can push the car (or jack up a tire and turn by hand) when in different gears to see if it's going in gear at all.