Fotiman - 7:11 pm on Jan 7, 2013 (gmt 0)

There's no MooTools or script.aculo.us or anything

In that case, you shouldn't need the noConflict() at all. If you remove that, then $ should be available to all your functions, assuming they are called after jQuery has been loaded (for example, called in the ready() method).

but '$' is "undefined"

I think it depends on when you try to look at it. If you're looking at it before jQuery is loaded, then that makes sense.

Do a [jsfiddle.net...] just with:

I did, and it works as expected. Are you seeing something different?

Based on everything you said, I think that if you remove the noConflict, and you don't try setting $ to anything, then you should be able to do this:
<script src="jquery.js"></script>
<script src="external-1.js"></script>
<script src="external-2.js"></script>
<script src="external-3.js"></script>

Then in your external files, your functions should have access to $ without having to do anything special.