Now that Apple has released OS X 10.9 Mavericks, you might want to consider creating a USB install drive for clean installs and future use.
If you're an Android whiz, here's your chance to earn some serious coin. But you'll have to code fast if you want the full $5,000.
Several users have reported an issue in which users experimentation with or inavertent modification of permissions on key system resources renders the system unable to boot.
Normally $36, this handy utility includes a "Windows to go" feature for creating a bootable Windows flash drive.
Check your chipset.
mac.column.ted: The trouble with creating bootable drives and discs [Part 2]
mac.column.ted: The trouble with creating bootable drives and discs [Part 1]
Apple offers downloadable, bootable TechTool Deluxe CD for AppleCare customers [Download link now working]
Intel-based Macs: The booting situation (#2) -- new partition format required; creating an Intel-bootable volume
BootCD creates custom bootable CD with a Finder!; Related bootable CD and copy volume follow-ups