In case anyone finds this as useful as I do, I've recently made an OS X version of my Instant Background Uploader which I posted about here long ago (for Windows).

It's a tiny no fuss utility to upload images from Clipboard to ImageShack.



On OS X, the Ctrl+Shift+Cmd+4 shortcut to copy a Selected Area to clipboard is especially handy in combination with IBU.

You can download it at the same place... http://www.cse.yorku.ca/~shuryork/