Presently, at home, I have a single, dynamic IP number (with 3 computers).
In the past, I've usually had (a) only one computer on the 'net or (b)
multiple static IP's.  I haven't yet looked into setting up multiple IP's
with my ISP (I know that multiple dynamic IP's are available at an extra
charge).  I'm not sure that more IP numbers are worth the extra expense
for my home connection, right now.

I thought that the thing to do would probably be to set up NAT.  But, I
recall that there are other, more service-specific, proxy options (e.g., I
recall an environment variable to set an http proxy server in web
browsers).

Is NAT a general, umbrella mechanism that tries to do everything
(necessarily failing when it doesn't understand the protocol it's
forwarding and the protocol carries IP addresses as data)?  Or is it a
general concept, encompassing such things as http proxies?  If the former,
what are people's recommendations on setting up proxies vs. setting up
NAT?  (Is there an overview of this somewhere---online, or in a book
somewhere---that I should go read?)

I really only want a few services forwarded.  In decreasing order of
importance: HTTP, FTP, ssh, and telnet.  (I don't need to support inbound
connections for any of those at this point---though it might be nice at
some time to support inbound ssh connections.)


  ``I probably don't know what I'm talking about.'' --rauch@math.rice.edu