Ubuntu is a free and open source linux operating system. It is based on another linux distribution, Debian, which focuses on stability and security. Ubuntu aims to create an easy-to-use desktop with new releases scheduled on a predictable six-month basis.
KeePassX is a cross-platform derivative of the open source password manager KeePass. It allows you to have all your passwords in one place, where it is securely encrypted and accessible through a master password and (optionally) a separate key-file. It can also generate passwords for you, with a specified length and use of certain digits. The idea is that you replace all your previous memorized passwords with longer more complex passwords stored in your password manager, and you bring the database file with you (on a USB stick) when you need it.
Make sure to make backups of your database file and don't forget your master password (for example, a sentence is easier to remember such as 'thesunisaharschmistress').
If you want to visit a website but you don't know if it's safe, using Firefox with NoScript is a good idea.
DuckDuckGo is a search engine which emphasizes privacy and does not record user information. DuckDuckGo's results are a compilation of many sources, including Yahoo! Search BOSS, Wikipedia, Wolfram Alpha and its own Web crawler, the DuckDuckBot.
Cryptocat is an open source web application intended to allow secure, encrypted online chatting.
Cryptocat is served via HTTPS, while also offering a Google Chrome application that loads code locally. Cryptocat intends to provide means for impromptu, encrypted communications that offer more privacy than services such as Google Talk, while maintaining a higher level of accessibility than other high-level encryption platforms, and furthermore allows for multiple users in one chat room.
Off-the-Record Messaging, commonly referred to as OTR, is a cryptographic protocol that provides strong encryption for instant messaging conversations.
It provides deniability for the conversation participants while keeping conversations confidential, like a private conversation in real life, or off the record in journalism sourcing.
A Pidgin and Kopete plugin exists that allows OTR to be used over any IM protocol supported by Pidgin or Kopete, offering an auto-detection feature that starts the OTR session with the buddies that have it enabled, without interfering with regular, unencrypted conversations.