The Imageshack Hotspot is a semi-transparent frog that sits in the corner of your screen. When you want to upload an image, just drag and drop it onto the frog! Also, if you don’t need it, you can send it to the system tray. (Although if you ask me, it makes a nice decoration!)
I used this for a while when the Imageshack Toolbar wouldn’t support FireFox 3, even with the Nightly Tester Tools.
The Imageshack Hotspot is a 3rd-party tool, not created by Imageshack, so use at own risk. (Although I had no trouble with it.)