I'd like to make this a poll, but don't know of a way of doing so.
Anyhow, we regularly get questions about chains and tires. No - this is not the winter riding forum, I'm talking about drive chains. So, here are the questions:
Speeds (7, 8, 9, ... )
Typical mileage (metric or miles OK)
Road or off-road use
700c or 26" (yes, I'm leaving out all the other sizes)
Primary function - racing, casual local rides, touring, loaded touring, off-road
Team + bike weight bracket - light (<290 lb, 130kg), med ( 290-360 lb, 165kg ), heavy (>360lb, 165kg) [do not include gear, as that is factored into "Primary function".]