Exploration at the earliest stages of the design process is an integral component of effective low-power design. Nevertheless, superficial high-level analyses with insufficient accuracy are routinely performed. Critical drawbacks of current high-level design aids include a limited scope of application, inaccuracy of estimation, inaccessibility, and steep learning curves. This paper introduces an approach to alleviate these limitations, thus enabling more effective high-level design exploration. A World Wide Web (WWW) based prototype tool called PowerPlay, which encapsulates and enhances these techniques, is presented.