No hack needed, I found it. This averages the current score with 500,000
`http://www.dualmonitorbackgrounds.com/themes/dmb/db.php
?j=499999
&q=39
&t=68.122.159.210
&c=500000`
I'm sorry, I tested it on this image to find the exploit -- http://www.dualmonitorbackgrounds.com/abstract/MyBalls.jpg.html . It originally had a rating of 1.1 with 17 votes, you probably want to change the db back.
There's no limit to how hight that number can go, because the maximum vote is controlled by the query attribute `'c'`. That's bad, and allows anyone to modify the query URL to make whatever vote they want, even one that's more sly and less obvious... (like on this one, for example: http://www.dualmonitorbackgrounds.com/abstract/Tentacles.jpg.html I changed its rating from 3.3 w/ 7 votes to 5.0 w/ 8 votes with some quick math).
In db.php, change `$units = $_REQUEST['c'];` to `$units = 5;` to make the votes max out at 5 and reject all others, regardless of the query value.