I just read an article about the Importance of anonymity on the web.. Is it possible to maintain anonymity using services like Ubuntu One, and are there any native system tools within Ubuntu that will help me to maintain privacy and/or anonymity? I'm using Ubuntu 11.10 64bit.
SnapOverflow
The measures you take to protect your privacy depend on the concessions you are willing to make in order to make use of different services. For example, if you decide to use Facebook, you will have filled out some info which is then visible to your contacts. Any FB applications that you use will have had access to some of your info and could just as well have recorded and stored it in a database elsewhere. If you use a service like Google Docs or Dropbox, you are giving your files to a third party and trusting that they will not breach that trust.
A lot of your privacy measures will be up to you and the information you supply, I don't think tools can help you very much. Sure, you could browse through a proxy but if you give information to a website, then that kind of defeats the point.
A few things you can attempt to do:
"Internet Privacy" is a very broad issue and some of the tools that can be used to track you are quite sophisticated, and some of the tracking tools do not have anything to do with your OS.
Here are some very broad suggestions
TOR
https://www.torproject.org/
Your ip address is only one piece of data that can be used to track you. I say this because a lot of people suggest TOR. Not that TOR does not have uses mind you, you should at least be aware of it's limitations as well.
If you are going to use tor with any reliability, you really need to read the documentation. Not just the installation guide, but all of the information, including the information of proxies and DNS leaks.
The tor project has very pertinent information on using tor, including this
https://www.torproject.org/download/download-easy.html.en#warning
In fact, the tor project advises you download the "tor bundle"
https://www.torproject.org/download/download-easy.html.en
Which includes tor, Vidalia , and patched applications.
Browser
Your choice of browser is also important. Some browsers (chrome) "phone home".
http://lifehacker.com/5763452/what-data-does-chrome-send-to-google-about-me
You should take the time to search the information your browser sends.
Browser settings
Your browser settings are important. Most browsers have a privacy mode, you should use it.
The issues here are cookies, flash cookies, html5 cookies.
It is possible for web sites to view your history and bookmarks ;)
Search engines
What search engine do you use ?
Take a look at this page:
https://www.ixquick.com/eng/protect-privacy.html
Passive OS Fingerprinting
Beware your IP address is not the only way you can be tracked.
See
https://panopticlick.eff.org/
technical details
http://www.ouah.org/incosfingerp.htm
If the above link is a little too technical, see
http://net.tutsplus.com/tutorials/other/http-headers-for-dummies/
The thing that "hurts" with these tools, the more you try to hide, the more you stand out. Try it, use a proxy server to filter the information your browser sends and you will be more and more unique.
Conclusions
It is extremely difficult to remain anonymous and requires education and diligence.
You can not be anonymous simply by installing an application, you have to change your behaviors as well (see the tor pages I linked).
Anonymity
For anonymity you can use Tor, which will make your real IP virtually impossible to detect. When you setup Tor you will use internet through a proxy, so all the information you send or receive (including Ubuntu One file transfers) will go through Tor and be made anonymous.
Security
For security, I believe there are some commercial antiviruses for Linux (though I don't really see a need for one, been using Ubuntu for years without antivirus and computer runs perfect).
You can also use a firewall, I believe Ubuntu runs UFW naturally. This will prevent people from breaking into your computer through ports.