So lately a lot of people and a real lot of businesses have started using
802.11 wireless networking products with names like wavelan, airport,
orinoco and other weird corporate brandnames.  In particular, I'm given to
understand that many current Apple products have airport cards/antennas
built in as a standard feature.  These are all the same product (pretty
much) and can all be made to talk to each other.

So these wireless networks are all over the place, and they usually connect
to the internet.  Certainly almost all businesses that have wireless also
have a T1 or better net connection, and more and more home users have DSL
or cablemodem and a wireless access point.  Some groups of people are even
setting up free wireless networks in urban areas and connecting them up to
their private DSL or cablemodem lines to provide free net access for
anyone who wants - check out, for example, the 
Bay Area Wireless Users Group.

Uh... I'll finish this later.