At home I have two computers, in two different rooms, both with internet access. My main computer is connected through a router that is connected to a cable modem, the cable modem is also connected to ...
You can use two Windows machines at once with a single keyboard and mouse without any special hardware. I had an extra laptop lying around that now connects with the same keyboard and mouse as my PC.
Still using only one computer? This might be the year that changes. You could use a netbook as a secondary laptop for taking into meetings or on business trips, for ...