After Smultron there is Text Wrangler
Wow.
All this, and for free. So much control, and yet the editing interface is clean and clear.
Evertime I wanted to change the apps behaviour I found an option to do it. While I might criticize some of the menu placement, the app is consistent across its own interface and what is there to complain about when you look at the price and realise there, uh, isnt one.
Seriously, this app would be worth at least $20 if not more. Its very full-featured. What with the no-cost, you should at least try it!
I would take away a star because the text-rendering engine doesnt work with Retina displays, but despite that very, very, very minor shortcomming, its early days and the app is very much more than that.
yoink about
TextWrangler, v4.0.1