Editor
Geany is an excellent free open source text editor for *ux, OSX and Windows
Context action
Geany allows the setting of a context action for the right clicking on a selection. An obvious use for this is to link to the php manual, but unfortunately the php manual uses - instead of underscore, so this script is used to launch it instead. Save the script in /bin or something and then set it in the context action in prefs (use %s to represent the selected text in the command). Having a script to launch the browser is a good idea anyway because we could later expand it to launch other URL's based on the selection content.
Colours
In the most recent version of Geany the single-quoted and double-quoted strings are now the same colour. I don't like this because I used single-quoted strings for keys and double-quoted for values and so like them to be different colours. Some other people feel the same way to as this issue about it was raised and has a solution which is to edit /usr/share/geany/filetypes.html from root and change the php_hstring value to string_2. Also edit ~/.config/geany/filedefs and make sure the string_2 colour is ox006600.
Linespacing
Another tweak I like in that ~/.config/geany/filedef configuraton is to set line_height=2;2; which spreads the text out vertically a little.