Shared tasks, appointments, reminders...

I would like to use Sandy in my office. The problem is getting people to USE Sandy. I would like to know if there is a way to share tasks/appointments and send a friend reminders to their Sandy account. Can I send a Reminder to my co-workers Sandy account and tag it with @daily? Will it show up in their daily digest? This would be great to help manage group projects as well as individuals stay on task. Thanks for your help!