CThruView Transparent Image Viewer - CThruView is a free transparent image viewer that allows mouse clicks to go through the image.
PiP for Mac - Always on top window preview similar to the popular windows only OnTopReplica
LayerX - An intuitive app to display transparent images on screen.
PiPer - A DIY Minecraft computer to build gadgets
PixelPerfect - Allows developers to put a semi-transparent image overlay over the top of the developed HTML and...
Galapix - A Zoomable Image Viewer zoomview.