[frio]

Ignoring the usual "vim", "emacs" etc., do try Sublime Text 2, if all you're after is an editor. So far it's proved unfailingly excellent for me :).

FWIW Chris stated in a previous post that Lighttable would be built on embedding CodeMirror, which, being web-based, should make creating cross-platform builds much easier.

[politician]

Hear, hear on ST2. I don't have to do anything more than let people see me use it before they switch.

[lordlicorice]

It's not just an editor. I use it for Python development. There's a plugin that uses Rope to give you completion, go to function definition, etc:

https://github.com/JulianEberius/SublimeRope

[kami8845]

I've been using Emacs for months both on Linux and Windows and it runs much smoother on Linux, its' intended habitat.