With the GL Image Browser, you can open a folder on your computer and look for all the pictures that are inside, even in subdirectories if you want. It is no iPhoto or Picasa clone, GL Image Browser is not meant as a tool to archive pictures, but as a tool to quickly browse through thousands of pictures to find a special one you are looking for.
If you left-click on a picture, you enter the full-view mode where your whole display is used to display the pictures. You can then use the arrow keys on your keyboard to go a picture forward or backward. Click again and you are back in the Requirements
PPC, Mac OS X 10.2 or later