Thanks to Gustav's work, quiz reports are now real plugins.
I have updated the Detailed responses report plugin.
You can download it here : http://moodle.org/mod/data/view.php?d=13&rid=96
Please, as SourceForge CVS is curently broken , don't use the "Browse CVS" link or you will get a very outdated version, use the "Download" link to get the latest version.
The install procedure is very simple, just upload the files on your server. No existing files are overwritten (unless you have a previous version of the report installed). No database change, no table added, no need to visit Administration.
A new tab will appear right to the Overview, regrade, Manual grading and Item Analysis tabs.
The plugin include a style.css file you can edit to suit your needs.
For the moodle users unfamiliar with this report, it display all your students responses to all questions in the quiz in a big (paginated) table.
You can download the data as an Excel or Text document.
For Moodle users unfamiliar with the detailed responses report plugin, I include a screenshot.