Don't download that type of file anymore. Most gnutella programs have an
option to filter out .rm or .mov files from your search results, so add those file
types to that filter. Don't forget to add the Microsoft types, .wmv and .asf.

Those types of media file are still useful on websites but on sharing networks
the spammers have switched to using these types of files because they can
be made to open your web browser to any site they choose, either earning a
few cents on ads or invading your computer with hostile software.