* put in checks so the user can't enter data that is clearly invalid (perhaps
  this will be done through debconf.

* do other sorts of network configurations (pcmcia, ppp)

* pppconfig would be a good starting point for the ppp udeb.  There is also an
  example in there of how to use pppd to detect a modem.

* Make netcfg-static smarter about default values, e.g. call ifconfig and
  parse.

* Ask for a hostname if the DHCP server does not provide one.