The Electronic Frontier Foundation’s Secure Messaging Scorecard evaluates popular communication apps based on privacy and security criteria and determines which are the best to use. You’ll quickly notice that Google Talk, AIM, and similar options are among the least secure, and it will explain to you why.

Remember, privacy is not all about you. Recall Dr. Daniel J. Solove’s article: by using secure messaging systems, you are respecting and protecting the privacy of the recipient as well as every person connected to the content of the message. We are more tightly interconnected these days than ever before, so the action you take to protect privacy affects the community as a whole. The Secure Messaging Scorecard is another great resource for learning how to use technology responsibly in an age in which information is easily abused and manipulated.

You may also enjoy the fact that FOSS apps such as TextSecure, ChatSecure, Pidgin, and RedPhone, are all ad-free, beautifully designed, and faster and more lightweight than most proprietary software.