I'm trying to get my Amiga 2000 online with a serial cable connected to a PC running Windows XP. I'm following these instructions, which glance over how exactly to configure Internet Connection Sharing with SLIP.
As you can see, I'm sharing my wireless connection. I set up a new "Incoming" connection, listening on COM1. I don't know if that is necessary.
I am certain my serial cable is functioning properly, because I have sent data to the Amiga with ADF Sender (adfsender.stoeggl.com/).
If anyone has successfully shared their network over a serial cable, whatever OS you used on your host box, please let me know. I haven't tried this with Linux, yet, but that is my next step. I just assumed it would be easier in Windows.
EDIT:
I set up a SLIP connection from Windows over my serial cable. Whenever I start to dial, then ping any address from the Amiga except 192.168.0.2
(the Amiga's IP) the ping requests show up in the pre-dial terminal on Windows. They all fail with 100% packet loss.