Data buoys are a widespread method of not only monitoring environmental parameters, but have a range of other applications: from surveillance to providing power for autonomous underwater vehicles (AUVs). The majority of data buoys currently in use are either solely powered by batteries, or they employ an array of solar panels to sporadically top up the battery power when environmental conditions are suitable. Less usual for data buoys is the use of wind power—though some successful hybrids of the two, such as the AXYS Technologies WindSentinel, also exist. As wave power technology matures, advancements in this currently underdeveloped technology could allow data buoys the option of using wave energy converters (WECs) as an alternative renewable power source. Data buoys could provide a small-scale application of WECs where many of the issues with harvesting such a stochastic and irregular energy source would be highlighted. The lessons learned in developing wave-powered data buoys could potentially be applied to larger, more costly wave energy applications such as wave farms or megawatt-level generators. This review considers data buoy projects currently in development—particularly those that look to incorporate a wave energy harvesting mechanism as either their primary or secondary power source, and their prospects, both as end-use applications in their own right, and as low-cost platforms to prove emerging wave energy technology for larger-scale use.