Microsoft just acquired Jellyfish - a shopping search engine based in Madison, Wisconsin. According to Jellyfish.com site

Jellyfish is the ONLY shopping engine to directly share $ with you. As a Jellyfish member, you’ll receive automatic savings on everything you buy. Think of us as a search engine for shopping, except we share at least half of every $1 we earn when you shop.

MSN Search Blog also announced this on their own blog

We want to welcome some new folks to the Live Search family - we recently purchased a company called Jellyfish.com, based in Madison, Wisconsin. Jellyfish has done some really innovative work in comparative shopping engines. We think the technology has some interesting potential applications as we continue to invest heavily in shopping and commerce as a key component of Live Search.

I wonder how it will help the Microsoft search engine on this new acquisition, are they building a shopping site empire?