It’s probably well-known by many people, but I just stumbled across Microsoft’s MSN Sandbox. It’s a bit like Google Labs (Google’s “technology playground”), featuring what Microsoft calls “incubation experiments” which may or may not “represent any particular strategy or policy”.
Most of the tools in the MSN Sandbox are well-known – some were even purchased as part of a company acquisition and just haven’t found their way to a release product yet (e.g. the Lookout e-mail search tool). Strangely, the site that referred me to the MSN Sandbox doesn’t have a reciprocal link – that was start.com – Microsoft’s new experimental site for RSS aggregation via the web, which I think I will be giving a spin over the coming weeks and will blog about some more if it turns out to be useful.