If there's one thing I'm diligent about, it's backups. Backup, backup, backup. It always must be said at least three times, just for emphasis. It's that important.
I use Apple's Time Machine for my general backup system; it's easy to use and robust. But I also like to have something to fall back on, especially when it comes to computer backups. If you have ever found yourself in the middle of restoring a backup because of a system failure of some type, you know how gut wrenching it is to discover your backup is corrupt and can't be used.
That's why I maintain multiple backups, as well as multiple backup methods. It may seem a bit extreme, but it doesn't hurt to be paranoid, at least when it comes to protecting your computer's data. I use Time Machine and SuperDuper in combination to create a robust backup system for my Macs.
I use SuperDuper to create bootable clones of my startup drive. With SuperDuper I can easily get back to work quickly should a drive fail or important data become corrupt. By just re-booting and setting the SuperDuper clone as the startup drive, I can be back to work in about the time it takes to restart my Mac.
SuperDuper is my personal choice for a clone-making backup application. I like it for its user interface, and ability to schedule the creation of startup clones. But it's not the only choice. Carbon Copy Cloner is another popular backup application with very similar capabilities. No matter which backup application you decide to use, be sure to get it installed and working right away on that new Mac.