Other - Find all words between $ signs

Hi,

I am trying to develop a regex that will find all words in a string that start and end with $

e.g. in the following string:
"Hello, $how$ are $you$ doing?"

I would want it to return either:
how
you

or:
$how$
$you$

(whichever is easiest).

Please could someone help.

Much appreciated!

James

Might be better to grab $how$ so any replacing you do will remove the $s as well.