Google does wonders: http://aurora.wells.edu/~wmccracken/
There's probably another way:
a person could have the desktop dial up, and have the laptop use a wireless interface through hardware ports from the desktop to wireless, to send and recieve data at a faster rate i think.....
edit: nevermind, stupid thought.. i'm wrong..i think...
well if you had skillz you could set up the computers to send a command to the other to access a file and when it recieves a file through the serial port then it runs a command to tell the computer to get an internet file and then the file is sent through the wireless serial connection to the laptop.. but is much complex..
i would suggest DSL. I was using Dial up for the LONGEST TIME!! i hated dial up!! hate hate hate hate hate!! DSL is yummy. mmmmm
With all the time and money spent actually doing a dialup transfer that way, you could've bought DSL for a month and tried it out.