One of the sites I run has quite a few high quality images on it (I get them from the PR companies)
Unfortunately , as happens so often, scumbags are hotlinking to a lot of the images. Now obviously I'm not worried about bandwidth costs, but I am rather annoyed with these lazy scum abusing images on my site...

With that in mind I've put in place a mod_rewrite rule to block hotlinkers and display an anti hotlinking image instead which appears to be working fine

The question is ...

Which domains should I whitelist?

As the site has an RSS feed anyone pulling that into an RSS reader service may be impacted, which I'd rather not do if I could avoid it

Thoughts?