HD 209458 and the Power of the Dark Side
  The rich wealth of observational data, and matching theoretical investigations, of the transiting planet of HD209458 stands in sharp contrast to systems for which only the radial velocity orbit is known. In this paper, I summarize the current status of these observations, and motivate a variety of projects that should be accessible with existing instruments. I describe observational estimates of the planetary radius, and discuss the relevant sources of uncertainty. I compare these estimates to those based on theoretical structural models. This discussion motivates the observational pursuit of three quantities that could be derived from measurements of the secondary eclipse: These are the albedo, the temperature, and the orbital eccentricity. I review the recent detection of the sodium D lines in the planetary atmosphere, and discuss ongoing work to search for molecular features in the near infrared. I also outline the use of the Rossiter effect to study the alignment of the orbit with the stellar equatorial plane, and transit timing to search for additional objects in the system. 
David Charbonneau