2) This software is only of use to a small subset of people, namely
  those who do or would use NetBSD for routing.

Sorry to disagree Charles, but it has another use: complementing in-router
filtersets by permitting the host to perform drop/allow of its own accord.
Additionally, it *LOGS* what its doing. This is extremely important to
anybody who wants to (a) ensure that loss of firewall doesn't compromise
service (b) track and pre-empt probe attempts.

-George