Occasionally, if you're at a rotation that's far away from your home institution (lets say you have a one month rotation in Fresno as a UCSF student), you may get some kind of assistance with a place to live for the month. (No idea if said UCSF-Fresno rotation has that sort of thing in place, but I know I've heard it in a few places). The school might keep a few apartments in the area, since it'd be rather difficult to find a place to just rent for a month or 6-weeks or however long your rotation is
I've never heard of a program offering a *stipend* for any sort of rotation though.