Desktop Groups is a simple app you can use to create folders on your desktop that can contain any number of files. Designed to help clean up the clutter on your desktop, Desktop Groups lets you create as many folders as you wish, add or delete files in a folder, and move the folder and all its contents around as you need. There is a free version of the app called Desktop Groups Lite, while the full version is sold for $5.99.
Installing Desktop Groups is easy and the app runs cleanly. You can create folders with any title you wish, then drag and drop files to add them to the folders. Similarly, opening the folder lets you drag and drop files to remove them. You can see what's in folders by hovering the cursor over them, and you can adjust the display of a folder's contents and the visual opacity of the folder (including having different background colors for each folder).
Desktop Groups will appeal to those who like to have a clean desktop and organize their files for quick access through an icon on the desktop (instead of digging around through the Finder). While it's a simple concept, many will find Desktop Groups a handy addition, while others will not think it is worth the money. That decision comes down to how organized you want to be and what that organization is worth to you. Desktop Groups worked fine for us.