Firefox test shows you archived pages instead of 404s

Mozilla's Firefox may be lagging behind Chrome and Internet Explorer in market share, but it promises something those two browsers don't — no more 404s. Mozilla launched a new project on its Test Pilot platform this week that replaces missing web pages with archived entries for the site in question, giving users a glimpse at what would've been there if they'd searched before.
When presented with a missing page, Mozilla's No More 404s add-on will give Firefox users the option to v