digiCamControl is a free Windows utility to control your camera settings remotely from your Windows PC via USB Trigger image capture via release button on the camera or remotely from your computer. It is a free and open source DSLR controlling application that's powerful, well-designed, straightforward and easy to setup.
Here are some screenshots to illustrate the features and user interface of this application:
Picture Style Editor
Exif Pilot
ExifTool
PhotoGrok
Free Shutter Count