This has to be the candidate for the shortest web URL evah. I clicked on a heavily truncated link in Twitter to be delivered to a site with a working web server with the internet's own version of the programmer's Hello World message: "It works!"
Nothing very special about that other than the fact that the address was just two letters: bi. Curious as to how you could get to a working website without a single dot, I had a look around to see who owned the 'bi' top-level domain. It turns out to be Burundi, which seems to have a single web server that directs accesses to addresses like 'gov.bi' to the same curt but cheery page.
Burundi's not very well off, so maybe they should give Bitly and TinyURL a run for their money (if there is any) in the URL shortening business.