Check which ports are open to the outside world. Helps make sure that your firewall rules are working as intended.
One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.
It seems that RPM is installed though (just checked, and it's on mine too).
It is not recomended to use RPM directly: http://packages.ubuntu.com/hoary/admin/rpm
although the reason seems to be just for consistancy... still it's the safer option.