In the post below, http://tinyurl.com/BXXRN and http://tinyurl.com/bxxrn direct one to the same page http://www.talkingpointsmemo.com/archives/007280.php. This is really weird, because at http://tinyurl.com they claim "Making long URLs useable! More than 13 million of them."

I assumed that the tinyurls were case sensitive. The five letters come after a / so they can be a UNIX file and, one of the reasons i HATE unix is that it is case sensitive.

But no, it seems that tinyurls are identified by 5 case insensitive symbols. This is weird because 26 to the fifth is only 11,881,376 < 13,000,000.

Oh I see most tinyurls contain letters and digits and 36 to the fifth is 60,466,176
giving tinyurl a few options left before their urls have to become slightly less tiny.

I was puzzled because I got one of the probability (26/36)^5 = 19.65% all letter urls.

Never mind.