I'm a big believer and user of cloud / web based apps and data storage. I use Google Docs, Google Reader, Google Sites, Blogger, Evernote, Engrade, iGoogle, Aviary and more. Web based computing allows me to have access to my data and files anywhere that I can get internet access, including on my smart phone. It also allows me to share data and information with others. I also like web based apps and data because it is platform independent - Windows, Linux, Mac - it doesn't matter. The web based apps also, in my experience, seem to run better on older, slower computers than native applications.
I'm also a believer in being prepared and having backups of my data. The services I use have great data centers and backup, but sometimes their servers go down, and sometimes I may not be able to get internet access.
I backup all of my work and data in multiple places so that I always have access to it, even without an internet connection. Here's what and how I do:
1. Google Docs - I use GDocBackup to backup my Google Docs. I also have Google Gears installed so my files are synced with my computer that way too. You can also export your Google Docs to your hard drive.
2. Evernote - I have Evernote's desktop application at home so all of my notes are backed up on my home computer. I also export the data once a week to an html and txt file for backup.
3. Engrade - this is an online grade book. I export my files once a week to Excel for backup.
4. Google Products - I also export my Blogger blogs, iGoogle Settings, Google Reader subscriptions, Calendar, email, tasks, and bookmarks once a week as a back up. For each of them, go to settings and look for the export command. Here's more information on how to export data from Google's services.
(I use Google Chrome so my bookmarks are synced between my two computers.)
All of the backup files are in a directory that is automatically backed up to SugarSync and then kept in sync on both my school and home computers. Sugarsync does this automatically, so it is no effort for me. I also have really, really important data (financial, digitized paper records, etc) on a flash drive in my fireproof safe. Just in case.
I also sync my Palm Centro smart phone with my Google Calendar and Google Contacts using Goosync. I then backup everything on my Centro by Hotsyncing it to my home computer. I also have a microSD card in the Centro that has a back up of my important files so that I can access them via my Centro, even if there is no signal to get an internet connection. I can use Sugarsync to access all of my other files via the internet on my Centro also.
My home computer's disk drive is also backed up to an external hard drive every day.
Some may say this is overkill, but all of it takes me about 10 min each week and gives me great piece of mind.
How do you backup your files and data?