Adobe Bridge File Browser in Adobe Photoshop CS2 and Creative Suite 2

Adobe Bridge can be quickly switched into a compact mode shown here, which floats on top of other windows and supports drag and drop to other applications. By clicking on the icon circled in red, the compact mode switched to ultra-compact mode. In this mode you only have a small toolbar taking up screen space (the area shown outlines in red), but one click slides out the thumbnail tray, so your image previews are always close at hand.