A few years ago my office was robbed. The thieves broke in on a Sunday afternoon and took all our computers. They were starting to haul away most of our CDs and other information when one of my employees surprised them. She called the police but they still managed to escape. There were two additional unfortunate circumstances that came with the robbery. The first was the fact that they easily managed to disarm our alarm system since they came through the roof (which we never thought would happen) and cut all the wires to the main control box which was right below their entry point. The second was that all our conscientious backing up of computer files was for nought because the tape system failed and did not warn us. We spent the next two weeks re-entering our data thanks to hard copies we kept on file.
The lesson from the whole fiasco was to use the most secure and reliable backup system available. After that, we did our backups much more religiously and checked every day that the system was functioning. Since then, data storage has come a long way. After personally trying a separate external hard drive for backup I have now made the switch to online storage. I have the feeling that there are probably lots of people in the event business who either are not doing this or are unaware that it exists. I cannot recommend it strongly enough. What happens if you store your backups at your place of business and the hard drive is stolen or the building burns down? It's still lost. Online backup prevents this.
There are other advantages. First, you can share files with anyone or nobody. You choose which files to share. Of course, this means sharing and permitting downloads of such things as images, videos, or complete proposals for clients or colleagues. Second, you can access the files from anywhere. This means that you don't need to transfer everything to your laptop. You can access it from anywhere in the world, even an Internet cafe, make any changes you like to the files, and upload the revised version.
The cost of storage is cheap and well worth it. I currently use a site called http://www.myotherdrive.com/. The cost is about $55 US dollars per year for 100MB storage. More is available if needed. Check it out. You just might save yourself a whole lot of grief.