If noone is already packaging it, I'll do.
RRD is the Acronym for Round Robin Database. RRD is a system to store and
display time-series data (i.e. network bandwidth, machine-room temperature,
server load average). It stores the data in a very compact way that will not
expand over time, and it presents useful graphs by processing the data to
enforce a certain data density. It can be used either via simple wrapper
scripts (from shell or Perl) or via frontends that poll network devices and
put a friendly user interface on it.
RRDtool is free software and comes with a GNU license.