I've developed a bot for gox trading (hosted on google app engine) which I've been using with reasonable success so far (avg profit 1-3% per day). I am considering opening it up to outside investors and want to get an idea of the demand for such a service. I will most likely settle on taking a percentage of the profits that it generates (as opposed to alternate pricing schemes).
It is certainly not as profitable [longer term] as simply holding at this point but it does offer the advantage of capitalizing on the near-constant noise (and is thus a good avenue for diversification). I will, of course, over time increase its efficiency and customizability but it is already reasonably efficient and customizable.