I operate under the assumption that every day when I power up my computer, all of my data is gone. For my ProTools audio recording computer, at the completion of each day's recording/editing, I copy the session to an external drive, and also copy it over the network to my everyday computer. As for photos, documents, etc., they get backed up from my C drive to my D drive as part of my periodic Acronis True Image backups. Photos also get backed up to my other computer and to a DVD that I can add to over time (may be the weakest link). I also copy my document folders to a USB flash drive periodically so things like my check book register and logon IDs spreadsheet are stored in at least 3 places. I don't do this all that frequently, as I know I can reconstruct the check book register from the online bank records if necessary (and I don't have too many transactions per month). As for programs I have installed, I just keep a spreadsheet of everything installed, in the event my primary and backup image gets destroyed and I want to re-create the same system state.