I occasionally take my kids (5 and 3) to daycare in a trailer. Most days we just walk, though, since their daycare is only a couple hundred yards from the house. :-)
FWIW, they love riding there in the trailer - it's a big treat for them compared with walking. I don't do it all that often because of the extra hassle of having to ride back to the house to drop off the trailer. It seems silly to take it to work with me, since I'm all of 200 yards into a five-mile ride.
The father of a little girl in my son's kindergarten class frequently brings her to school in a trailer as well, although I don't know if he's commuting on to work from there or not.