Customer Relationship Management is a must for any retailer or service provider that can afford it, it's not cheap since it requires storing massive data. Storing the data isn't the big issue, but rather organizing and analyzing the data in such a way that is useful for your company. They most definately have a system that analyzes my behaviour and tries to figure out why am I on their site. How can they use my bahaviour patterns and make me purchase more? Amazon does a good job at implemeting a CRM system. I usually go on their site to either buy business or history books. I'm constantly getting e-mails from Amazon either recommending other books or asking me if I want to sell those that I've purchased. Whichever it is, they keep me engaged.

For whatever reason they always recommend more history books than business when in reality I've bought more of the latter. I guess in that sense Amazon doesn't get me 100%. They give users the option to 'like' different items in order for them to get a better idea what one looks for. Another company that does this pretty well is Netflix. Everytime I watch a movie I rate it because they obviously compile this information and can make better suggestions for me. So far I've rated 561 movies through them and that doesn't include all the ones I see in theaters before Netflix gets them. I'm really happy with Netflix's CRM system because their suggestions are usually pretty accurate. There has been a few flukes but generally they are pretty good at it.