Try Imageshack - you don't have to sign up.
1st save the picture to your computer (My pictures or somewhere)
Then hit the browse button on the imageshack page and go to where the pic is located on your computer and doubleclick it.
Then hit the upload button on the imageshack page.
Then wait ...and when it comes up - copy the line that say's 'forum code' and paste it into the box that comes up when you hit 'image insert' at the top of the Spiritual forums message post box.
(note. The first time you hit 'insert image' in the SF box you
may have to press a bar that comes up along the top of your page and 'allow temporary scripted windows'...and then do it again' for some reason) .
http://imageshack.us/