While lots of people use the bucket object for shifting data in series, it's computationally useful for calculating first and second derivatives for streams of data.
I also tend to use the object quite a bit in situations where I desire a running average over some history of events. Here's an example that calculates the average of the last 8 floating point input values:
The cycle object
(please list things that you believe to be errors or omissions from the existing refpage)