
Picasa is a great photo organizer by the good folks at Google. They recently added a web album feature that allows you to upload photos to the web and create individual albums by subject. When you click on an album, you can view a slideshow of all the photos in that album.
Check it out my first albums at picasaweb.google.com/rono359 or click on the photo album link in the right column of the blog. The best part of all, Picasa is free.