Link shortening service

Twitter's tweets must be 140 characters or less.  That means that the first link in the numbered list below cannot be transmitted as a tweet but all the characters are needed to get directly to the target book at Amazon.com.  Also, anyone trying to enter a link into a mobile phone really appreciates a link with only a few characters.  Aha!  A new service, a new market, a new way to get a few coins.  The first link shortening service was founded in 2002 but now there are 180 of them.

Here is an interesting and educational article from O'Reilly Radar blog on the subject of link shortening services and some of the pros and cons of them today. The basic idea is that one pastes a long link to be shortened into a window on the shortening service's site and uses the short form created by the service as a substitute for the original link. 

Google has a shortening service: Goo.gl

3 links to the same book on Amazon.com look like this:

1. http://www.amazon.com/gp/product/B001VNC95O/ref=s9_kindo_gw_ir05?pf_rd_m=ATVPDKIKX0DER&pf_rd_s=center-1&pf_rd_r=13YH10XSJAMKFTCGN51M&pf_rd_t=101&pf_rd_p=1278185902&pf_rd_i=507846
2. The above is a link to Mark Epstein's book "Psychotherapy Without the Self".  Here is a buried or masked link to the same book.
3. Here is a link to the same book that has been shortened by Google's link shortening service, Goo.gl   http://goo.gl/0Jcg

As made clear in the O'Reilly Radar post, the Goo.gl link will only work as long the Google link shortening service is "up", that is functioning and connected to the Internet.  Being Google, they try hard to fix things so that their service is always up.