Find the age of a page/tab (the date/time you originally loaded it)
This extension will tell you the date and time a page/tab was loaded.
One example use case: You have a page showing the number of views a photo has received. If you've let the page sit for a while, you can duplicate the page to see the current view count and then use Page Age on the original tab to see exactly how much time has passed. This would tell you "Ok, in the past 23 hours, there have been 48 new views."
Feel free to fork/contribute: https://github.com/bzle/Page-Age