Set one up as host for "Internet Connection Sharing" - W98 or later. The
client can be anything. Connect using a "crossover cable" if both have
Ethernet adapters. That's the cheapest.
Otherwise, consider wireless networking. USB or PCMCIA adapers for 802.11b
are coming down in price all the time, and I've seen a pair of Actiontech
USB adapters offered for around £50 (UK). www.dabs.com