Lowering Website Memory Footprint

Hi, I recently got this message from my web host "Your sites are using more memory than your server has available. When this happens, the kernel will kill the heaviest user until it can get the memory allocation under control. This will continue until you do one or both of the following: A) Consult an experienced PHP/MySQL developer requesting that they assist you in lowering your site(s) memory footprint B) Purchase an addon/upgrade providing you enough memory to accommodate all of your sites. Until such time as one or both of those are done and your sites are no longer using more memory than your server has access to, you will continue to run into such problems. The likelihood of this causing permanent damage to some of your sites files increases each time it happens." I need somebody who can help me lowering my site's memory footprint. Website description: It's a gaming server list with approximately 5000-10000 visitors per day. I believe the voting page ([login to view URL]) is the main thief for draining the VPS of its memory including other pages where the majority of visitors goes to. I can give you more logs etc concerning the problem if you are interested. Please give me a brief idea of how you intend to minimize memory usage on my site to make this from not happening again. Thanks, John