DesktopCollage for Mac

From Aksima - Andreas Kummer:

With DesktopCollage you can easily arrange images ("stickers") right on your desktop. You have complete control over the layering of the stickers and DesktopCollage even supports transparency, so stickers can take on any form - in the transparent regions you can still see the desktop.
Since DesktopCollage is designed to stay open all the time, it also makes up a fast, compact image viewer that is always at hand and that lets you display your images without disturbing window elements like title and scroll bars.
For instructions and a screenshot please visit http://www.aksima.com.