So this didn't make it into the talk, but was in the hidden slides...
not positive this is a "low" but a friend suggested it, so here you go.
Goes like this:
Request gets logged
Something malicious gets written commonly something like a one line PHP backdoor
1. Use an LFI vulnerability to browse to page get shell
<a href="http://websec.wordpress.com/2010/02/22/exploiting-php-file-inclusion-overview/">http://websec.wordpress.com/2010/02/22/exploiting-php-file-inclusion-overview/</a>
2. Wait for an admin to view logs and do whatever you did (XSS)
Can also do fun stuff like this (TNS Logfile injection in Oracle)