Keeping intruders out of your system is half the challenge; making it impossible to find your valuable data is the other. We've rounded up 10 downloads to help you do just that.
The SecureClean commercial package, $50 (£30) or 15-day free trial, has a wide range of functions arranged around the task of scrubbing unwanted data, from deleted files to Explorer search terms. It produces detailed reports, turning up quite a number of tiny file fragments cluttering up space, some of which contain readable data. It also adds a right-click menu option to erase a file securely, always a nice touch. However, I encountered a fairly serious flaw: When the scanner reached a file with non-English characters in the name, it would simply hang. This problem can manifest in surprising ways; I discovered it because SecureClean balked at the foreign-language templates in a desktop publishing program I use. This is a known bug in SecureClean 4 running on Windows 7 64-bit machines, and the vendor plans to fix it in the upcoming version 5.
Finally, sometimes you just want everything gone, such as when you're recycling or donating an old system. CCleaner has a drive-wipe function, but you might also check out the descriptively named Darik's Boot and Nuke aka DBAN. This is a straightforward program, as it comes as an ISO disc-image file. You burn the image, and then boot a computer with that disc; the utility then seeks out and destroys all data on the computer's hard drives.
My personal pick for a password tool is Sticky Password, but KeePass is a very close second and might jump ahead over time. TrueCrypt offers all the features I want in disk encryption, at the unbeatable price of "nothing."
For secure erasure, I use a feature of Directory Opus (a Windows Explorer replacement) for actual file deletion, but CCleaner's long list of other functions makes it a keeper as well.
See also: How to secure your mobile phone