The agreement includes the two companies completing full integration of Microsoft's Windows Media Technologies with ThingWorld.com technology, seeking shared marketing arrangements that target leading media, entertainment, music, sports, and consumer brand companies, the companies said.
Details of Microsoft's investment were not disclosed.
The financing decision follows an announcement in December that the two companies had formed a strategic alliance to integrate their multimedia products to send interactive video used to display copyrighted images over the Internet.
The Newton, Massachusetts-based Thingworld.com makes design software, which creates what it calls "Things"-animated logos, scenes, and interactive puzzles and games.
The company also develops an Internet Media Network that aggregates and syndicates content to the Web's top portals and communities, bringing content to online consumers, much like a television network or movie distribution company, the company said.
Thingworld technology is already used by Geocities, a company that helps members set up their own Web sites.