You can secure and locate your mobile phone in case you lose it or it gets stolen by using different available Android market apps i.e. Norton, Kaspersky, AVG etc. They let you send an instant message to your phone and lock, locate and / or wipe everything from your device completely. On the con side, you have to pay for the app, and in some buy the yearly subscription. Anti-Theft For Mobile by F-secure is a free app that lets you lock, locate or wipe your mobile device by sending a command remotely. Another pro of this tool is that if the SIM is changed, the new number would be reported to you.
The commands are simple:
Remote lock: #LOCK#<your code>
Remote locate: #LOCATE#<your code>
Remote wipe: #WIPE#<your code>
A great free tool which is easy to install and use, protects your confidential information against loss or theft by lock, locate and wipe options.