I just installed a recent Vista build on my dev box, and I noticed a new set of options to add a custom search engine in IE 7. Which got me digging. For your browsing pleasure, here are some links:- This page describes the current list of providers, and what else needs to be done on the missing providers. The requirements are simple - the search engine must support queries based on the OpenSearch 1.1 standard. - The IE blog contains a little bit of history around Amazon and Microsoft working together on this standard. - The A9 developer blog also contains some interesting details.