Before I bought my RV, I rented an RV through Cruise Canada for a one way positioning for 9 days at $25/day through Cruise Canada. My son and I traveled from Calgary to Toronto to drop the RV off in June and had a blast. The next year, I bought one down in Vermont and brought it back home to Canada (much cheaper than buying it at home).
Here's the Cruise America site for "repositioning" and other kinds of deals:
Cruise America: RV Rental Hot Deals
I've priced out an RV rental before, and it seems to me it would be cheaper to stay in motels/hotels. I think they also have repositioning in the fall from Alaska to Canada or the lower 48. That would be an excellent one way trip to take!