Dan Lyke has posted Drizzle, a response to Microsoft's Hailstorm. Drizzle is an attempt to kick-start the process to develop an open alternative to Microsoft's planned service. One problem users and developers face is that they are entrusting their or their customer's personal data to a single entity with no proven track record of reliability or respoinsibility. Drizzle allows users to sign up with any trusted third party or even to run the Drizzle server locally. This could be important in a corporate environment where the company may want to control where their employee's data is kept by running a central Drizzle server. I can't imagine too many HR directors being happy about their employee's job titles, purchasing capabilities and salary brackets being in another company's possession, no matter how many privacy agreements are signed.