Photo-Lux 3.6 was available as a giveaway on April 25, 2010!
Photo-Lux is an extended image viewer with a lot of image processing features such as RGB/ Brightness/ Contrast/ Gamma - correction, auto white balance, red-eye reduction etc.
It supports every file type you can imagine, and some you can't (including almost all Camera RAW formats). It contains slideshow and HTML album maker. For JPEGs, TIFFs and RAWs it uses EXIF-tag to auto rotate the images.