Getting a webpage’s update time

Often you want to know a specific webpage’s update time, here is the tip:

1. go to the page you want to check.
2. type: javascript:alert(document.lastModified) in the Address Bar
3. press enter

You will see a message box that displays the data and time of the last modification.

(source: http://www.microsoft.com/windowsxp/using/helpandsupport/learnmore/tips/kelly95.mspx)