Is there a tool for measuring content freshness?

[PeterTroast]

i.e. crawling a site to identify last date of new or changed content? Thanks.

[eatyourveggies]

Many sites will have "Modified Since Http Header" enabled. If so, then when looking at a page you want to check, type this into your address bar:

javascript:alert(document.lastModified)

But that won't work on all sites as some may disallow javascript execution in that manner. But also if it's a dynamic site and the web owner hasn't configured their Modified Since Http Header properly, then you'll get incorrect dates anyway.

You can see if a website has the Modified Since Http Header enabled:

http://www.hscripts.com/tools/if-modified-since/index.php

You can use the internet archive to look at previous versions of a website (unless they've disallowed this in the .htaccess):

http://archive.org/index.php

A cool tool I use to alert me to when a competitor (or any website) content is updated is:

http://www.changedetection.com

Enjoy