So, let's say you have a serious virus infection or your computer is on its last legs. Now, you have no choice but to back up your data because you already did not(which you should always). As you will have to reinstall your operating system all your original data may be lost. So, you are wondering, wow, I have all my bookmarks and E-Mail that I will loose through my browser and how will I back that up? Well if you are or were using Mozilla FireFox Browswer(which you should be as it is more secure than Internet Explorer) and ThunderBird E-Mail program(which you should be as it is generally more secure), then you are in luck cause you can use the following to back up all your E-Mail and bookmarks and reintall these quickly.

"MozBackup is a simple utility for creating backups of Mozilla Firefox, Mozilla Thunderbird, SeaMonkey, Mozilla Suite and Netscape profiles.

It allows you to backup and restore bookmarks, mail, contacts, history, extensions, cache etc. It's easy way to do Firefox backup, Thunderbird backup"

You can download this freeware program from here:
http://mozbackup.jasnapaka.com/download.php