This is a simple python script that shows the last connect time of puppet nodes. It currently displays them in red / green depending on if they've connected in the past 30 minutes.
Warning: This code needs a lot of work, but it is in working condition.
The simplest way to install this would be to go to your puppetmaster, and run this:
$ wget --no-check-certificate -O /usr/bin/puppetlast https://github.com/gregarmer/puppetlast/raw/master/puppetlast $ chmod 755 /usr/bin/puppetlast
The output looks something like this: