My obsessiveness just came in handy. Tracking a shipment from the USA (living in Canada), it hit a customs delay that required my input. Sad thing is that no one called me to inform me, and the only reason I noticed was that I checked 14 times this morning. The first 13 were ok. The 14th was not. [Edit: clearly it is likely that their call-centre had me in some queue somewhere for the call, but I called them before they had the chance to call me.]
So I called, spoke to a very helpful woman at FedEx who e-mialed me the paperwork. Completed, scanned, e-mailed back, and now is clearing customs. Might still be delivered on time, though tomorrow seems more likely.