So you flying to Vancouver all relaxed like when you decide to take a glance out your little window. Normally you would notice a some mountains, water, fields, houses... any of those would be normal, but yesterday on just such a flight you would have noticed two fighter jets. From the Globe and Mail comes the report:

An Air Canada flight was escorted into Vancouver International Airport last night by two NORAD fighter jets in response to a potential threat.
The story later on goes to say that this type of thing has happened 1,800 times since September 11, 2001.