[IMG] BBCode File Caching (copying hotlinked files locally)

[eviltechie]

I had an idea for my forum, and was wondering if anyone had heard of such a thing, or if I'd have to do it myself.

I'd like to modify the way [ IMG ] BBCode tags are handled. What I'd like is for them to cause the hotlinked image to be copied to my server and subsequently loaded from my server as opposed to fro mthe hotlink location.

Basically, say if someone did this:
[ IMG ]http://photobucket.com/blah/somephoto283786.jpg[ /IMG ]

I'd like it to copy that file to my server and automatically change the BBCode to the following:
[ IMG ]http://myserver.com/imagecache/7283466.jpg[ /IMG ]

The BBCode would not try to copy locally files that already exist on my server, so after the first copy and BBCode update, it wouldn't require any additional processing.

The reason for this is often people post photos that either exceed their bandwidth allowance, or that they later move or delete, causing the thread to be full of broken images.

Has that been done? If not, would anyone be interested in doing it? I may end up doing this myself, but would rather not duplicate an existing project for the sake of time.

I know members could just use the attachment feature, but a lot of people don't like to take the time.