I was riding my trike, on my way home from work, this evening and had an interesting experience. First, to set the stage, it was a bit cold, about 12f, and there is still flowing water no the streets. Anything that is not flowing is frozen. In fact the water beads on my trike are actually ice beads.
I was riding home and I suddenly realized my left brake lever would not move at all. I had been thumbing (just tapping; but not enough to make pad to rotor contact) the right one without thinking about it; but I had not used the left one other than at a stop sign about four blocks behind me. I lightly pulled the left lever for no reason than to drag the pads a bit to dry them out and the lever would not move.
Now that the trike is back inside it is working normally. Fortunately there was no call for a panic stop (of course, on ice it wouldn't have stopped anyways). Like I said, the unexpected.
Yes, it was quite cold.
Taken on Sunday