Fun with XSLT

Hi Guys, Well i;ve been slaving on with my PHP XML endeavors and i'm loving it, just finishing the meaty parts of my XSLT for dummies book too. I have a question which asks "is it possible?". Using XSLT I can collect specific parts of my XML using something sexy like <xsl:template match="umbungo">. Lets say however, that I need to use XSLT, but I would want the user to select which element they request. In other words, they are given a form with options and that form can manipulate the .XSL file. Now I know it could be done in a lengthly manner by just opening the XSL file and manipulating it like fopen or something like that, but is there a way to somehow embed the contents of the xml into the php code (like using <<< EOF for html), and being able to substitute the template match string for a variable ? Any ideas ? Thanks Gamesmaster, Matt