Here at hozzamedia we use Coda. A brilliant IDE for coding in PHP, HTML, CSS and JS by Panic. Amazing software (especially when coupled with Transmit [their File Transfer client)).
However, I’ve never been to keen on the default syntax highlighting, and after using a Dreamweaver themed syntax highlighting for so long and feeling traitorous. I’ve built my own syntax colouring theme (in the old Coda 1 called a SeeStyle), called a SSS file.
My theme is based on various themes all over the net, feel free to use. Its easy on the eye and makes coding easier.