How can I distribute a standalone Python application in Linux?

I think I can take for granted the presence of a recent Python interpreter in any modern distribution. The problem is dealing with those libraries that do not belong to the standard library, i.e. wxPython, scipy, python cryptographic toolkit, reportlab, and so on.

Is there a working Linux counterpart to, say, py2exe (which, by the way, I have never tried)?
Is there a free, opensource one?