Quite simply the biggest selection of music, film, literature, software etc. you will find on the web. Definitely not always the cheapest direct from Amazon itself but the private seller Marketplace plugs that gap sufficiently for all the cheapskates. The extent of their catalogue is the stuff of dreams for other similar sites and the service is invariably top notch.

Regional sites for the major markets allow for a more personalised experience and with lots of additional tools and handy features the websites exude experience - these are the big-boys of e-commerce. If no one else has it, at least Amazon will list it and someones bound to be selling a second hand copy!