API: DirectX 5.0(JetLag1999) vs. SDL 1.2(JetLag2003)
Fullscreen Only (JetLag1999) vs. Windowed or Full Screen (JetLag 2003)
Different sets of "Lucky Charms", although most are present in both.
Since I'm sort of between projects at the moment, I'm thinking about doing a JetLag2004. This time, the API is Direct3D. Talk about overkill.