My years on a Sun keyboard spoiled me, so I remap backquote to escape (much more easily reachable than now-standard Escape location). Also Capslock to control and swap backspace and backslash. Everything I use more frequently is closer in. :)

I have capslock as control. My work computer has the ESC key, but it's out of reach. My ipad keyboard has no escape, so I've been training myself to use ctrl-[. Works ok, I don't really notice the difference anymore.