Sublime text. Mugs, It has tabs and they can be dragged to their own window.
SublimeText with package control. It destroys Coda 2. The only thing Coda 2 has over Sublime is working off the server, but then again this is bad practice anyway.
but Sublime is $70...
Not if you have a development server.
Eh, not really. It just bugs you from time to time when you save. Every 50 saves or so it shows an alert asking for you to purchase. It is kind of like winrar.