DS1302 realtime clock - pulldowns required?
Just for the record, works fine without any pullups or pulldowns.

RANDOM NOTE: Does very strange things if the power (VCC) pin is not connected.  I managed to get everything wired correctly the first time except I had a loose connection on the power pin, and because it has it's own battery thing is still on but gives somewhat systematic but garbage data.  Very confusing until I figured out what was happening.