The account space at DH (and all other professional, established webhosting companies) is to be used for webhosting, not for file storage. Yeah, I know - When does webhosting become storage and vice versa? It's a doosie.
Unlike many other companies DH do have a file storage system that is separated from your 'main' webhosting account. I can't recall the pricing structure in place off the top of my head but I remember it being on a 'per Gig' basis and dirt cheap in comparison to the available file storage businesses I looked at earlier this year.
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