No, this is not a real Sinatra error :).
This is the personal homepage of Elad Meidar, a web developer and an entrepreneur specializing in Ruby on Rails. I hang around in Israel, and i am currently having the best time of my life over at Fiverr.com
I am a proud member of RailsBridge, Helping new Rails developers get into our world and also contributed a few Patches to the Ruby on Rails core.
There are many uses for shell accounts, i prefer to use them for my legal needs only (MySQL, mail bouncing…), and although some people misuse this utility quiet ofter, i still think people be familiar with it.
Check out the free shell services
You're seeing this error because I think it is funny.