Comment Security is a Process (Score 3, Insightful) 314
I see that many comments have done a good job pointing out the paranoid mindset of the questions in this post. It's true, if you're absolutely worried about hiding your data from the FBI, CIA, and NSA, you are either doing something so illegal that I don't want to help, or you are delusional and paranoid. However, reading between the lines, I think you've just seen too much FUD about security. If you really just want security that's "good enough" then you can get it by following some of the simple best practices. Here's some things that have been found to help in most environments:
1) Passwords are pretty good. Use a different password (fairly long, somewhat complex) on each different site and use a password manager (put that on a non-networked system if you're concerned), instead of trying to memorize dozens of different passwords.
2) Separate important and unimportant systems - if you have an online banking account, don't access it from the same machine you surf the web for "warez" on.
3) Use virtualization technology to "sandbox" dangerous activities. If you're researching viruses or malware, or browsing unusual web sites, do that in a virtual machine with snapshots. Destroy the virtual machine or restore to a "known good" configuration frequently.
4) Turn on firewalls, run anti-virus, and use registry/configuration cleaners frequently. If you're blocking any inbound connections to your network, you're safer. If all files you download are scanned, you're safer. If you regularly scan for known exploits and malware, and remove infections or destroy the system, you're safer.
5) Use encryption for sensitive information. Full disk encryption on your traveling laptop would be a great start. Use disk or file based encryption on sensitive documents, and ALWAYS use SSL when transmitting over open networks (that means ssh instead of telnet, FTPS instead of FTP, etc.). Encrypt backups as well as primary data.
6) Keep your systems reasonably up to date and follow recommendations from your software vendors about best security practices.
I'm sure there's a thousand other tips that would help, but you're not paying me, so this is where I'll stop.