nagiosexchange.org/Categories.7.0.html for some windows and other plugins and stuff.
Most bb plugins can be used in nagios.
When I setup bb, I found it inferior to nagios, since it didn't have a "parent" directive for hosts. That means, the hosts where just that, a bunch of hosts in a list. But I don't want a list of hosts, I want a map that shows hostA connects to Hostb(switch port) which connects to hostC(switch) which connects to hostd(another switches port) etc. With nagios, I have a status map that looks exactly like the network and how it all physically connects together, including the eth0 on a pc.