I used to use smush.it years ago. I've since been using pnggauntlet & pngoptimizer to compress my image files for my forum & site, what about the rest of you?
You should give one of those tools a shot, it can result in some significant image size savings in most cases, and I should add that those tools produce lossless results. Not to mention you also save on bandwidth and that pagespeed is now a determining factor in google searches.
I was actually thinking about that earlier.. I would think they have hotlinking protection and if you were to be caught trying to use them as a cdn they may not like that too much but I suppose if you needed it badly enough that it's worth a shot..
I don't know, we used to embed movies from there. There was a problem with them not always being available from some reason, but other than that it worked. But I really only asked because it's in the search box on your screen grab.
A very simple way to compress the images you need to compress is to use the images given to you by GTmetrix as the images to use to replace what ever it wants you to replace ...
run your site through their performance analyzer, then it will tell you what images need to be replaced and it will actually give you the images to use in their place.