Other route to consider is to use VMs. That way you can just delete them
as you tire of them. Also you can try something like Gogrid.com which allows you
setup virtual servers over the internet. You can make as many or as few as you
like and only pay for the time that they run. It is very resonably priced and
you can set them up in minutes. You can make Windows, Redhat and Ruby on Rails
servers right now, but there will likely be more in the future.