Canadian startup Tungle.me solves one of the most annoying business problems: scheduling. Scheduling meetings with those external to your organization (meaning you can’t just look on Outlook Exchange and see their availability like you can with colleagues) is a time suck. Not only do you have to go to your Calendar tab and look for available times, make time conversions and block off potential time blocks, but you also have to send out a meeting invitation once the time is set. Any assistant can tell you this takes up a significant part of his/her day.

Enter Tungle.me which streamlines and automates most of this process while syncing with Outlook, Gmail and now even LotusNotes (this is a tough one to maneuver)! While Tungle.me is currently a pre-revenue company, the feature set it offers is a compelling platform for additional services that businesses would pay for.
Tungle is addressable to a huge market and would most effectively reach enterprise customers as a plug-in or add-on to existing scheduling clients (i.e. Outlook). What comes to mind is an Outlook plug-in that launched at DEMO called Gwabbit.
Obvious buyers: Microsoft, Google, maybe even Salesforce.
With Google Voice to take calls and Tungle to schedule your meetings, the modern-day executive does not really need an assistant anymore.