Andy Edmonds has an excellent post up on the Live Search blog about the new LinkFromDomain operator offered by Live Search, and how you can use it and other search operators to craft interesting and useful Search Macros.
As Andy explains, the LinkFromDomain operator lets you find all the sites that a particular site links to (outgoing links). Conversely, the LinkDomain operator can be used to find all sites that link to a given domain (incoming links). While it is fun to play with these, what's really cool about them, as Andy points out in this post on his blog, is that you can combine them in interesting ways and save them away as Search Macros, in essence creating your own little search engine that you can bookmark and share with others.
For example, here is a macro I just created to search the community around Om Malik's blog: http://search.live.com/macros/rvp/gigaom. Its definition is simply:
linkdomain:gigaom.com | linkfromdomain:gigaom.com | site:gigaom.com
Simple, yet powerful!