These list products from many different companies in one place and can be a good source of sales for your company. With the exception of Froogle, the sites mention above will take a percentage of each sale that is generated through their site. Froogle, provided by Google is free at the moment. The sites offer varying ways of maintaining your product listings with them. Usually you can upload a database of your products to their site.

(Froogle.com, BizRate.com, Shopping.com, NexTag.com ,Yahoo Shopping, Ebay.com, Amazon.com)