Yes; last winter. Unfortunately it froze in 1st gear so it took me forever to ride home. Once I thawed it I lubed all of the pivoting points and then sprayed the whole works with a silicon spray. It helped, but the derailleur still froze a couple more times, hence my decision to leave it in 4th while parked. That experience was part of the reason I bought my IGH/belt drive bike... I wanted a 4-season, low maintenance commuter. Since I mostly stay on the middle ring anyway having only 8 gears was fine with me, and the Alfine is a nice hub.

I still have a couple of derailleur bikes, but I park them for the winter.