Webkit browsers do exist on other platforms. They're far and away the best-performing sorts of actually-usable (in terms of supported Web features and ability to render real pages in the wild—sure, lynx works, but...) browsers on low-end machines, should you have to use one, to the point that they may be viable on a machine that's otherwise basically incapable of using the modern Web at all (which confirms for me that there's some fundamental, deep-down plumbing reasons behind why Safari's so much better on battery life than Firefox or Chrome-based browsers)

None of them are Safari and I can't vouch for how they are as daily drivers long-term, but it's nice to have one semi-up-to-date engine around that still kinda works on bad hardware (and by "bad" I mean still several times stronger than my workhorse many-tabs-browsing multi-tasking machine circa 2003—you'd be amazed how strong a machine has to be these days before trying to use the Web at-all normally in Chrome or Firefox is anything but terribly painful).