I recall using SLIRP back in the day with an dialup ISP that provided shell accounts in the base package, but charged extra for PPP (IIUC this was a fairly comm

I recall using SLIRP back in the day with an dialup ISP that provided shell accounts in the base package, but charged extra for PPP (IIUC this was a fairly common business model). With SLIRP I was able to access internet directly from my PC without paying for PPP access.