I have been using CS 3 Bridge to download. When I do I not only rename but embed the original file name in the Metadata. Plus at the same time I have template with all my copyright info written at the time of download plus any general keywords.
For renaming I put them into their own folder and a sub folder of originals of client last name and date. (Example Smith062307.crw0001) From that folder I can create proofs or web images which are saved into another sub folder. Any Photoshop work is saved into it's own sub folder called PSD. All print images are saved into even another sub folder called Prints. All emails and scanned contracts are saved into another sub folder called Extras.
Now to major right brainers this sounds like a lot of work but it really isn't and look at it this way. When I have first downloaded the images I can create a backup CD of original images with the same file names that everyone will see. When I am done and ready to burn the final master file to a DVD I have all the originals, work files, print orders, and paperwork in easy to find folders.
I am not unemployed, I am an Artist!!