i'll also put my hand up.. i have lost control of my trx before, just the once. was heading to see my uncle in wagga, i missed the turn off to wagga and was on another b-highway heading towards the hume and i had no idea where i was going or that i had missed the turn off.
there was loose gravel on the road that must have been a half assed effort at filling a massive pothole, i dont know if there was signage to indicate a potentially dangerous situation (i.e. the slippery road sign) but i just saw the pothole and swerved to miss it, slid on the gravel, the car fishtailed spun probably 3 or 4 times and i ended up down an embankment stopped only by a barb wire fence.
my girlfriend and i were very, very lucky to have escaped without injury and my car lucky to escape with minimal damage (broken screw tabs on the bumper and a few scratches from the barb wire fence)
once side of the road was a cliff face, the other side which i ended up on, i narrowly missed a telegraph pole. also very lucky that there was no traffic in either direction.
the speed limit was 100, i might have been doing 110 max..
was the scariest thing that ever happened to me and i realised how very very lucky i was to come out of it unhurt. it certainly woke me up a little with my driving style/habits.. you can never be certain of things, and as budge has pointed out above, even on roads we know.