Chris and Marie want to move a tree from *somewhere* to *somewhere* so the neighbours can't see Chris in his tutu (maybe you should cut that last bit XD, or make their intentions marketing orientated where they're trying to draw customers in). The tree is x m tall, the ramp they want to move it down can be described by equation y = blah and the height of the damaged roof can be described by equation blah (maybe use an inverse cos graph or something to make it a 'specialists' question).
You could go all integration on the '08 students sorry asses and get them to find the max possible height of the tree, etc.
Astronauts are running out of air. Volume of oxygen tank question could lead onto a rates question finding out how long the air will last (will they have enough air to be able to wait for the orbital tragetory they need?), which could lead onto a trig question where they re-enter Earth's orbit, which could lead on to a vectors question about landing.
More random scenarios... hockey game, moving trucks, basketball game (opponents have rigged the goal during half-time @ 1 end so the ball is slightly larger than the ring and can't go through..?), playing chess on a train (train is going up hill etc, 1 player accuses the other player of cheating, the other player said the piece moved on its own and denies cheating ...question about friction, vectors, mechanics etc ...was the piece really light enough to move forward on its own as the train went up the hill?).
I can't think of any complex numbers scenarios, but then again I hate complex numbers. Maybe some phenomenon where the data defies current knowledge ...black holes, something travelling faster than light, ummm... for some reason the bermuda triangle came to mind.
Hope that gets the ball rolling a bit for you
