How about Synapser?
Synapser is the first and only Automated SEDO (Search Engine Dynamic Optimization) Application in the World. By using the Synapser SEDO Application you will no longer require manual time consuming, costly SEDO dynamic optimization services allowing more gratifying and creative use of your time and resources, and it works in all languanges and pages on your site 24/7.
How can i use it?
Simply paste the Synapser client script on all your pages and/or templates, seed the first keywords on your Synapser control panel interface and then manage its behaviour; for example, you may choose to make some keywords static while others continue to be dynamically harvested, much like the "hold" button on a "one-armed bandit" and you are ready to go!
How does it work?
Our research team constantly analyses the behaviour of the most important search engines the Synapser algorithm adapts your site to take most advantage of them. When a visitor is sent to your web site, Synapser harvests the keywords which your visitor used to reach that page and then serves them up woven into that page to all subsequent visitors, (within user manageable title, meta-tag, description etc.) including web crawler searches, so improving ranking.