Command & Conquer: Renegade

The first (and to date, only) first-person iteration of the Command & Conquer series, Command & Conquer: Renegade puts you on the ground as GDI Commando Nick "Havok" Parker in a series of missions to stop the Brotherhood of Nod from developing an army of Tiberium-mutated super-soldiers. It features a reasonably lengthy campaign spanning a variety of locales, some fairly impressive graphics in an age of Quake 3-based shooters (the same "W3D" engine was modified to become, of all things, the SAGE engine that powers Generals and Tiberium Wars), and a multiplayer mode that in addition to being, in my opinion, one of the greatest in a shooter to date, introduced the world of PC gamers to freely-controlled vehicles in multiplayer (including flying ones). It also features an early look at EA's now long-standing tradition of terrible widescreen support.