The launch of enables people to search their email, personal files, web history and instant message conversations, in addition to the web.
The desktop search application is a free downloadable tool based on Google's search technology and matches new features unveiled by MSN global chief Yusuf Mehdi earlier this year, although MSN is not expected to launch its new search services until 2005.
Customers can use the new tool to search all their desktop files such as Microsoft Outlook and Outlook Express, as well as website history in Internet Explorer and instant chats in AOL Instant Messenger.
It is the latest chapter in the search battle for supremacy following MSN's announcement in September of a new-look search and results page and a $100m (£55m) investment to develop its search offer.
But Google is bucking the recent strategy of MSN's rivals, which has been to take services away from the desktop where MSN dominates and on to the web. Moves have included Lycos UK's launch in September of a virtual hard-drive for its email customers, which allows users to drag and drop files from Windows directly into a new online file storage drive as well as being able to access email and SMS tools.
Google's own Gmail also seeks to unite its search services with email on the internet.
Meanwhile, , which allows users to search internet or desktop documents, claims it has gained 1m unique users since launching in July.
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