I remember when I moved back to Montreal from Toronto that Budget had a fleet of cube vans available for one way travel. However, since I was in Montreal when my stuff was in Toronto, it ended up being much cheaper to rent a truck (20foot Hino) from Montreal and drive it to Toronto(in a snow storm!!). I don't know if they offered the service to Ottawa. If you can't get a one-way rental to Ottawa but you can drop off in Montreal, let me know. I'm about an hour and a half to Ottawa and could drive you back, provided you supply the Tim Hortons coffee!

I'm always up for a drive!
Eric...