Click the Photos button at the top of the conversation window, or open the "Actions" menu and click Share Photos. A shortcut is to drag photos from your computer directly to the messaging area, and then click Start Photo Sharing to invite the other person to view those photos.

The other person either "Accepts" or "Declines" your invitation. If the person accepts, you’ll see a confirmation message, and a photo panel will open to the right of the messaging area, both in your and your friend's message windows. If the person declines, you’ll see that message, and the photo panel will not open.

When the photo panel is open, just drag photos onto it from wherever you have them stored on your computer—your desktop, your “My Pictures” folder, wherever. It’s that simple. Drag and drop.

Both you and your friend immediately see the photos in the photo panel to the right of the IM area. You can continue writing messages as you look at the photos. “Such green grass!” “Is that your foot???” etc.