I've set up a small image & file attachment quota for all registered users. In the past, we had the Imageshack plugin that worked most of the time, but since the forum upgrade there hasn't been an easy way to upload images quickly from the board. All Registered (non-Foundation) users have 5 megabytes of space to upload images.
I know it isn't much, but it's not intended for long-term image hosting. If you need a picture hosted long term (say, for a build thread, signatures or glamour shots), then there are a lot of uploaders and file hosting services out there for that. We won't delete anything that isn't objectionable, but you'll run out of space quickly if you're using this to park images. But if you're selling an item or have a quick question and have a photo to go with it, then by all means use our server.
Images can be managed in your UserCP. And Foundation Members have 25 megabytes of storage. Hope this helps!