Download Rawzor
(Beta v0.41, Windows only)

Rawzor uses lossless image compression to compress camera raw images with zero loss in image quality or meta-information. Compress your photos with absolutely no change in the original raw file.

Save upto 20% to 60% space
Supports almost all raw formats
Totally lossless, get back the exact raw file, every byte of it

Latest from Rawzor Blog (March 2, 2009)
Rawzor adds Support for 5 New Raw Formats and 54 New Cameras
Screenshot
Rawzor Screenshot (on Windows Vista)
Results
Compression ratio depends on a number of factors like the camera model, image content, noise level, quality of in-camera compression etc... these results were prepared from a 0.4 Terabyte collection of raw images. See list of supported formats and cameras.
(Click on images to enlarge instantly)