The underscore makes it an invalid hostname. :-(<p>It is accessible in google cache, except _why's answers are images, which are not cached.  Aaargh!  So close.
<a href="http://74.125.113.132/search?q=cache:QtwetYZV3HgJ:_why.usesthis.com/+http://_why.usesthis.com/&#38;cd=1&#38;hl=en&#38;ct=clnk&#38;gl=us" rel="nofollow">http://74.125.113.132/search?q=cache:QtwetYZV3HgJ:_why.usest...</a><p><a href="http://tools.ietf.org/html/rfc952" rel="nofollow">http://tools.ietf.org/html/rfc952</a>: 
"A "name" (Net, Host, Gateway, or Domain name) is a text string up  to 24 characters drawn from the alphabet (A-Z), digits (0-9), minus sign (-), and period (.)."<p>See also: 
<a href="http://en.wikipedia.org/wiki/Hostname#Restrictions_on_valid_host_names" rel="nofollow">http://en.wikipedia.org/wiki/Hostname#Restrictions_on_valid_...</a>