If you're looking for a plainly simple image viewer, you've come to the right place: here's VJPEG, a photo viewer that displays images right on your desktop. After installing it, VJPEG takes over the native Windows image viewer and opens all JPG, BMP, and GIF files on the desktop. Images are opened as is, without any additional frames, windows, or interface.
VJPEG offers a very original way to display photos. With this program, you can drag and move images around the desktop with the mouse and close them with a right-click. Additionally, you can resize images (just for viewing purposes, no actual size changes are applied) by sticking the image to the left screen edge and dragging it. Other tools available in VJPEG include rotating, zooming in and out, adjusting levels, and even sending images by email.