Recommendations for personal computer security when running Linux, for and by myself. You are free to use these as guidelines if you please. Many of these are specific to laptops, which are more likely to be stolen or lost.
Items in bold are considered required & items in italic are pending.
- Set a BIOS password required for boot (does not protect data per se but as a deterrent for casual thievery)
- Use an encrypted home or system partition(s).
- If encrypted home is not possible, use an encrypted USB key to store your documents & data, keep separate when not booted up. Also, see  notes below.
- Use encrypted swap
- Select "Use a master password" in Preferences->Security (a reasonable compromise to not saving any private data, a real pain)
- Use extensions: NoScript, SSL Blacklist
- Drop history save length to 2 days
- Set Preferences->Advanced->Network offline storage to 0
- Select "Use a master password" found in Preferences->Privacy->Passwords