My most recent close call was on the Skykomish on a mini washington road trip (early december 2006)
I was wading across a small sandy side channel. The water was only about three inches deep but the sand was very soft. I was making my way carefull a cross when the soft sand got deep and I went in past my left knee into the sand. I tried to pull myself out for 15 minutes with my free leg, but I felt like I was going to dislocate my knee. I gave up on trying to pull myself out and started digging in the sand to try and free my leg, this did not work either as the sand was backfilling as fast as I could get it out.
The sand was so tight around my knee that it felt like concrete. I was a little bit concerned so I flagged down the next jet boat and got them to help me get out. It took the two guys in the boat and all of the strength in my right leg to finally free my left leg. I was very surprised my wading boot did not get ripped off.
Thank god I was on the sky where there are alot of people around. If I had been bushwacking in some remote river somewhere:
what a way to go like being stuck in a leg hold trap, waiting for hypothermia at nightfall and hoping beyond hope for someone else to come along.