Another download program to add to htaccess

[spacemanspiff]

I know absolutely nothing about this kind of stuff, but someone on this board posted this a while back

RewriteEngine on
RewriteCond %{HTTP_REFERER} !^http://(www\.)?yourdomain.com(/)?.*$ [NC]
RewriteRule .*\.(gif|jpg|jpeg|bmp)$ http://fullpagead.com [R,NC]

I use it briefly for stuff like alltheweb.com's image search crap. I wasn't sure what the implications for google would be so I removed it, but I seem to recall that it just blocked everything instead of trying to catch each domain that's hotlinking.

Any of you code gurus care to comment?

SS