You're welcome.
Dh works as a sysadmin for a domain hosting company, and the problem came up with one of the customers who couldn't understand why she exceeded her available bandwidth on the 4th day of the month. It was because someone hotlinked to a small file (4 kb) and it was viewed something like over a million times. Sucks for her - she didn't want to fork over the cash for additional bandwidth to get her through the rest of the month.
In my case, I have around
1400 photos in my online photogallery, and if I allowed hotlinking... It could be a whole mess of problems.
The other thing to know about hotlinking is that, in my experience, when you add a new subdomain to your site, it messes up the hotlinking controls - I had problems viewing my own images on my own site with links that previously worked. To fix it, disable hotlinking and then re-enable and it works just fine again.