There is an editor called Sublime Text 2 which is beautiful to work with! It doesn't have all the bells and whistles of a major IDE, but most features are there and many others can be installed - using TextMate bundles. I think Python is it's scripting language, so additional features can be added this way (I believe?).
Of particular note is a distraction free view and multi-selection - both really cool! There's an unlimited trial but the product itself costs $59 dollars. I can also click a file on the left to get a (full) preview of it, without necessarily opening the file
I have also just discovered Zen programming - but I suppose most web developers have already discovered this? For example, to generate a table with five rows of four cells each, I can just type
table>tr*5>td*4
and press some key combination (such as Ctrl-Enter) to generate the table. Fab! It can also be installed with Sublime Text 2. Andy.
P.S. the red arrow in the screenshot is pointing at a mini-map of the current page.