Before the RR-net became the defacto standard for networking on a Commodore 64, many people would connect the C64 as a terminal to use a PC's internet connection. I thought that this was a bit cumbersome myself, and I did not connect my C64 to the 'net until I bought an MMC Replay + RRnet cartridge. I actually use a wireless bridge so that effectively, my C64 connects wirelessly, but thanks to external hardware.
With the lack of an RRnet-like cartridge for the VIC-20, I suppose that using a PC as the external device is a necessary evil in this case. It would be nice one day if we could find a way to compile the Contiki OS to a fully maxed expanded VIC-20 (32K + 3K). But with the lack of native VIC-20 networking hardware (aside from a modem), some feel that just using a PC as an internet device is a form of cheating.
I personally don't feel that it's cheating, an external PC to connect to the 'net is no different than using an RRnet. It's just that the latter is a far more elegant way to do it. With an external PC, you have to boot it and start the software.
edit: Schema posted this picture of how tweetver connects to a PC:
My wireless bridge + RRnet on the C64 takes up less space. On top of that, you need an old-style PC tower that still has an RS232 or LPT port nearby. If there is ever an RRnet-like cartridge that gets made for the VIC-20, I'll definitely be the first to buy it.
It's fairly evident that this is a nullmodem that does basic receive/transmission of data. Sydbolton received a bit of backlash and said the following in response:
In response to those saying this is "cheating" - I submit that I never once claimed this was a native TCP IP situation on the VIC. I used a small PC "box". To say it's cheating to communicate would be like saying any wireless device that goes through a router is cheating since a router is essentially a computer (usually) running Linux. If I put that code into a box that was connected directly to the VIC nobody would say anything but alas.
It might be a bit cooler if IP65 (or something like it) was ported to the VIC-20. On the plus side, it did garner publicity for the VIC-20.