NAT Router for other purposes

I use a Linksys BEFSR41B to connect both my PC and my Linksys printer server
together while I am using my Internet connection. This way I can use the
Internet and any of the three printers supported transparently with nothing
but selecting which printer I want to use.

And, since I use a company laptop as my PC, the hardware changes often. The
Linksys insulates these changes from my ISP connection.

Oh, in addition, I never see DOS attacks against my PC or my printer server,
since the Linksys does not respond to connection attempts.

Does this mean that I am an evil person, trying to cheat the ISP? Should I
be charged $5/month to use my printers which cannot be accessed from the ISP

I think not, and, not.

Evil? This isn't about good and evil, right and wrong, or moral and immoral.
This is about business. Your circumstances are very common, and very
mundane. The real questions you need to ask yourself are - what are your
ISP's Terms and Conditions, which you agreed to when you signed up, and are
you willing to face the consequences for violating them, if you are?

I think that trying to inject any sense of "good vs evil" into a technical
or business discussion is counterproductive, particularly when no one is
doing anything unethical. There seems to be some sense amongst users, that
folks at ISPs who make ultimately unpopular business decisions are bad
people. The real question is, are the unpopular decisions ultimately
profitable, due to increasing revenue, or do they backfire due to their
unpopularity, and end up costing money.

- Daniel Golding