I think it depends on how much you're going to use it.
The Dreamhost Terms of Service state:
Note that they call out proxy scripts as frequent offenders for using too much CPU.
OTOH, some people have reported success in using proxy scripts for occasional personal use.
Do a search for the term proxy using the search feature of the board. Use "forever" as the time limit and search on "All Forums". You'll find a gold mine of information on the subject.
This thread seems particularly useful.
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