I'd really like to see this as well, but I'm kind of waiting to see how the GL Plug-in API changes with the pending 1.8 release. Until someone makes a plug-in for phpESP, you can wrap phpESP surveys and result fairly easily in to a GL site. Just install phpESP as a standalone application on your site and build your survey.
For each survey, create a php file with the following;
Text Formatted Code
/* phpESP survey page */
require_once('/path/to/lib-common/lib-common.php');
$sid=2; // id number of phpESP survey
// $results=1; // uncomment this line to display the results instead of the questions.
$display = COM_siteHeader('menu');
include("/path/to/phpESP/public/handler.php");
$display .= COM_siteFooter(true);
echo $display