I work in NetBeans and thinking to move to nusphere. Is it possible to hightlight current variable everywhere in the text? Not just all variables, but the one which I have selected by cursor.
This is how it works in netbeans: for example, I have huge source code. I click on a desired variable and that variable is highlighted with yellow background everywhere in the code automatically so that I can easily see where it occurs. It is very helpful for me, so is it possible to highlight a selected variable everywhere in the code just by clicking on it? Thanks.

Yeah, nusphere PHP-Ed do that. Anyway I think is not in the entire text, but in the current scope only (which is ok for me). As you say it's a very helpful feature.

Where can I turn it on?

under settinges->editor settings check last entry named 'Autohighlight'