gvim, or straight VI if gvim isn't available.
I have used a *lot* of different operation systems over the years, and only two editors have been available across all of them, VI and EMACS. I don't get on with EMACS, so VI it is.
Example, even my now ancient series one TiVo PVR with it's 54MHz PowerPC cpu and 16MB (yes sixteen megabytes) of ram has vim on it