Companies that give users an alternative to Microsoft Office include JotSpot, AdventNet, Silveroffice, 37signals, and Haansoft's ThinkFree. In 1999, ThinkFree conceived the idea of a Web-based word processor, spreadsheet, and presentation application online, but in March, 2006, Google acquired Writely, an online word processing startup, and introduced its own online spreadsheet. Google's interest has validated ThinkFree, and other online word processors, such as Wiki from Jot Spot, Zoho Writer, Rallypoint, and Writeboard, are now available. They require no downloads and charge no fees to individual users, and there are also competitors to Excel, including JotSpot Tracker and NumSum, among others. The Office suite is under attack by Office and Zoho Virtual Office. Microsoft will enter the fray with Windows Live services that will offer software as a service, but Ray Ozzie has made no mention of an online strategy for Microsoft Office, which, says a venture capitalist (VC) interviewed, has incredible market share. However, says the VCs spokesperson, that also means Microsoft does not have as much flexibility in changing the business model or pricing structure of the product. Joe Kraus, CEO of JotSpot, has signed up over 2,000 companies for JotSpot's online wiki-like spreadsheet, calendar, and document services, and 37signals Writeboard word processor and Basecamp project management software support real-time collaboration and group chat, as well as the more conventional features of office productivity tools.