Well, this isn't a typical thing since it's a data demo of a product, but I usually have four hours worth of meetings a day which range from project status updates to configuration to process mapping. The IT world is very meetings heavy and doesn't always allocate time wisely.
I fucking hate when people feel the need to schedule meetings on a Friday AND always use the entire time allotted for the meeting despite the fact all of the agenda items for said meeting were addressed in the first half of the meeting.
That's when you start throwing out some bullshit about how you're going to circle back and touch base next week, then something about synergy and just leave.
That would be far too obvious for Microsoft to have a close prompt, wouldn't it? Of course they don't.
You might find a tool that someone has made to do this, but personally I don't trust a lot of these in terms of security.
Only thing I can think of is that when you boot up you create a new message with some random text in the email address and body, that way if you accidentally close you'll get a prompt to save or not. But you'd have to do this every day...