Sure, people might snicker if they hear you've been taken out by something as seemingly benign as dryer lint. But, seriously; due to lint's high flammability, it can happen. Too much lint build-up inside your dyer can lead to a good old-fashioned dryer fire. And too much lint outside this appliance can do the same thing, especially if it's piling up next to, say, a water heater with a pilot light, like it is here. You should keep a radius of several feet around water heaters and furnaces free of combustible materials, such as paints, solvents, and, yes, dryer lint. If you notice lint build up, make sure your dryer vent pipe isn't cracked. If it is, replace it immediately, or patch it up with some foil tape.