[ratdude747]

My dad and I both are avid bicycle mechanics... and we use:

WD-40: My dad uses it for chains. I use it for chains once in a while. Also used for reviving dried seals in Presta valves and pike pumps.

ATF - I buy whatever happens to be cheapest (currently dextron-mercron mix). I use it for chains via an oil can. I also use it in 3 speed hubs, in freewheel mechanisms, and as a general de-gunker for cleaning old gunked up bearings and the like. I even have a plastic crystal light tube of it that I soak really crusty parts in. Once in a while it gets used as a cutting oil.

White Lithium grease- Used for packing loose/caged bearings, press-fit things (headset cups, square taper cranks, etc), sliding clamps (stems and seatposts), and heavy threads (bottom bracket cups, freewheels, track cogs/lockrings, crank threads). Also used to pack coaster brake hubs and to coat new brake/shift cables.

Not quite a lubricant, but PB-Blast often gets used for dealing with rusty things...

Back in my days as an FRC student, 3-in-1 was used by both former teams to cut stuff. Both teams used whatever grease happened to be donated for transmissions and the like; 1747 used white "food grade" grease; 2783 used black "ford/lincoln" grease. We had no issues either way...