I usually use Bridge CS3 to quickly go through the RAW pictures. Even though Bridge CS3 is faster than CS2. But it still takes some time to generate the thumbnails from the RAW (.CR2) files. Just found this FREE RAW thumbnail viewer. It’s a plugin to windows explorer. You can download it here.

The software is capable of previewing the formats:

* Adobe (DNG)
* Canon
* Hasselblad
* Kodak
* Leica
* Mamiya
* Nikon
* Olympus
* Pentax
* Ricoh
* Samsung
* Sigma
* Sony

The speed is very decent, here is the screen shot of one of my RAW folder
20071130 rawviewer RAW Thumbnail Viewer   Free