Skitch is one of my favorite Mac utilities. It lets you capture an image (either a screen grab or iSight snap), add markup such as text & arrows, and share it on Flickr, .mac, or Skitch.com. I’ve been using it instead of the OS X’s built-in screenshot.
Until now, you could only share individual images by providing the URL. Now, you can specify whether an image should be public, private, or hidden. The default, ‘secret URL’ still lets you share an image, as I have done here, but it won’t appear on your profile page. Any images you specify as public will appear on your public page.
My profile is at http://skitch.com/mike3k/.