Note this was written by Lou Montulli who also wrote the amusing post about "The Origins of the <Blink> Tag" [1]
[1] http://www.montulli.org/theoriginofthe%3Cblink%3Etag
I didn't know about the about:about url, and have since found a number of amusing and useful links, for example:
Chrome:
chrome://site-engagement/
chrome://net-internals/#dns
chrome://net-export/
chrome://indexeddb-internals/#
Firefox:
about:mozilla
about:memory
about:robots