Webapp Mixin is a social calendar that accepts short messages describing not only what you're doing but when, and shares that info with your friends. Plan and propose events or enter where you're going to be when with Mixin's drop-down box on-site, or wish for things or events (which have no specific time). Alternately use Mixin's short Twitter-style one-line commands (in the format of
what @where when, like "Rock Band @Adam's at 7") to enter events via SMS or IM. You can also let your friends know where you are for a possible impromptu meet-up with Mixin. Check out a video demonstration of how Mixin works after the jump.