Smart newbs use Notepad++...
Hobbiest use Komodo Edit:
http://activestate.com/komodo_edit/features/
Pros use Komodo IDE:
http://activestate.com/komodo/features/
All three are based off
Scintilla editor component. Komodo is built upon the mozilla framework and is cross-os compatible. Hands down the IDE is better than anything mentioned in this thread.