12-15-2010
This is the "batch renamer" I use for my photos, modified as a "generic" and assuming a Sony A390 camera was used. (You can easily edit the BAT file for your camera & edit any suffix preferences etc.) It renames the files with the format yyyy_mmdd_datetime_cameramodel, making the photograph readily identifable based on date-time shot and which camera was used.
The exiv2 program is what actually performs the "initial" rename, with the yyyy_mmdd_time portion, the BAT file, using "generic" MS-DOS syntax, adds the camera model suffix and makes sure that the JPEG extension, all lower-case, is the extension. (EXIV2 probably can do this, but I was unable to figure out how, so I had the BAT file do this--again, using "generic" MS-DOS commands.)