Followers of Yahoo! (NASDAQ:YHOO) know that the company's been on a shopping spree recently, buying up some of the best and brightest small Internet companies. This weekend brought yet another purchase, as word leaked out that Yahoo! had acquired a company called Del.icio.us.

What's Del.icio.us, you ask? I didn't know at first, either. It turns out that Del.icio.us is a "shared memory" site, where folks can share their favorite Internet bookmarks with one another. When users add a site they like to their Del.icio.us list, they can "tag" it with their own custom keywords, making those sites easier to find for users with similar interests. According to Reuters, it is a service that feeds into the Web 2.0 idea, which posits that the Web is moving toward sites that focus on collaboration among users.

Interestingly, Reuters pointed out that Amazon.com (NASDAQ:AMZN) was one of Del.icio.us's venture capital funders. Del.icio.us only employs nine people, and the acquisition price is apparently so low as to be unworthy of note when it comes to Yahoo!'s financials. Still, it looks like another smart buy, and a wise trend overall on Yahoo!'s part.

Other recent Yahoo! moves in the area of community-based sites include its swallowing up Flickr, a photo-sharing site, and its recent acquisition of another small collaborative service, Upcoming.org.

It's clear that Yahoo! is working hard to offer hot services that will lure users from formidable competitors like Google (NASDAQ:GOOG) and Motley Fool Inside Value pick Microsoft (NASDAQ:MSFT). Yahoo! may have its work cut out for it -- and there's always the challenge of getting acquired services quickly and easily integrated -- but the company's investors are likely glad that Yahoo! is trying to spearhead some of the Web's hottest trends.

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Alyce Lomax does not own shares of any of the companies mentioned.