Our information is hardly safe in today's mobile world. A researcher recently highlighted the vulnerabilities an improperly secured Blackberry causes, and who doesn't remember Paris Hilton's hacked Sidekick?

With Yahoo reporting how a used phone is a treasure trove of private information, it helps to know how to keep everything on your smartphone or PDA safe, even if you no longer use it.

So what can you do? Head over to this comprehensive guide on mobile security. Aside from some useful articles, there are also links to security and anti-virus software.