I don't know when you're planning to implement this, but I have a couple of other suggestions concerning file encoding which would be useful for people doing some work in different languages.

First there should be a way to somehow limit the list to most frequently used ones /it will come in handy later/. I'd have ISO-8859-2, Windows-1250 and UTF-8 instead of hundreds of encodings available now, 99% of which I won't be using in a million years.

Now that we have a shorter list of options let's think about where to use them. My first suggestion is in the status bar next to line:character information. Current encoding is already there so why not use as a place when we can change it instead of opening Settings > IDE settings? A simple right of left click would pop-up the list I mentioned earlier. Selected encoding should be applied to current file only or to the whole editor /two different lists/.

A second place that would be useful is Open using option in file context menu. This would also open a short list of selected encodings.

I'm sure I'm not the only one that would find these useful.

I totally agree on these ideas. I had also in mind writing some of those suggestions.
I have to deal with different encodings all the time and I was getting tired of having to set them every time in the global settings.

This shouldn't be too hard to implement into PhpED, or is it?