So, I was sad to discover that I couldn't register on randimg because their CAPTCHA system was down, but I found another rotating images site that I thought I'd share in case anyone was interested!

It's called SignAvatar. I'm using it for Eva's avatars at the moment, and it seems to be working pretty well - or I haven't encountered any problems yet, at least. The only thing I wish I could change is how many images you're allowed because currently the max is set at three. xD