Today you can find comparison shopping tools anywhere you go (google, yahoo, etc) but what I really like about Pristine Planetis that searches on Eco friendly products. You can also find, coupons, keep learning on ways of living green and customer reviews! The motto is:
Browse. Compare. Review. Shop
So for instance, you want to invest in a water filter you can get a comparison of all the different options you have out there plus pricing...
It is one of my guilty pleasures!!
Give it a try!