FWIW, my ISP gives me, along with my email account, 25Mb of web space. Generally, when I need to post pictures in forum, I just scale them down, host them in my space, and link them in the forum. That way I'm sure I'm the only one responsible of the picture being there, nobody can take it down without further notice, and if I run out of space -has happened a couple of times- I just delete older ones. Sure enough, some links somewhere will lost the photos, but hey, I did it for free.
Sure enough it is easier for the readers as they just see the pictures without having to click on links and wait for huge images to download.