Adobe's DNG Converter can convert any RAW format supported by the Adobe Camera RAW plugin, and the DNG files look and behave in just the same way as the original files. You often get smaller file sizes, too. For example, the 25Mb RAW files produced by a Fujifilm FinePix S3 Pro are shrunk to about half the size.
It's not much to look at, as you can see from the screenshot. But it's simply a conversion utility – there are no editing, enhancement or other tools. You simply give it a list of RAW files you want to convert, tell it the location where you want the DNG conversions stored and leave it to get on with it.
The DNG format hasn't really caught on in a big way yet, and camera makers like Canon and Nikon still produce cameras with their own unique RAW file formats.
There are some issues with DNG files, too. Although the format is supposed to be 'universal', it comes in many different flavours - a glance at the DNG Converter's file format preferences will give you a clue - and other applications may have particular DNG file requirements which you'll need to investigate.
Aperture (Apple) supports DNG files, but only if it natively supports the camera that produced the file anyway, so there's no point in converting more esoteric formats for Aperture using the DNG converter.
The idea of the DNG format is great, but the waters have become muddied and the industry has adapted to proprietary camera formats pretty well, so maybe it's had its chance.
