You could use ConTiki OS instead. The C64 version isn't as polished as C64 OS, but it's not bad, and it's entirely opensource. Of course it's a bit of abandonwa

You could use ConTiki OS instead. The C64 version isn't as polished as C64 OS, but it's not bad, and it's entirely opensource. Of course it's a bit of abandonware ATM, but it had lots of features: a web browser, an IRC client, a Twitter client...