Hey, I wrote that article! LOL!
That was more related to getting really old Macs talking to Leopard, but now all Classic Macs are shut off!
Snow Leopard can share using FTP, which means you could share back to a Mac Plus easily with Fetch.
One cool thing about sharing with FTP is that it "Shares a Share" unlike AppleShare. In other words, all mounted drives, including network drives, are available to the FTP client. That is really cool. Imagine a Mac Plus pulling directly from an iDisk or other share it couldn't natively get to.
The downside of FTP is it's not disk/GUI based sharing. You can't mount and run apps off of it like AppleShare.