I have more watches than I do bikes. But the coolest timekeeping piece that I have is the JLC Atmos. The clock never needs winding; it has a capsule that is filled with a special gas and temperature variations cause the capsule to expand and contract. The capsule is connected to a chain which goes to the mainspring and the expansion/contraction winds the movement. A single degree of temperature variation is enough to wind the clock for approximately two days.
This one is a 'baby Atmos' (model 526-5) and was made in the 1950s.
