Well, I realize changing a skybox dynamically isn't an easy task right now, but this is a feature I'd like to see.
During certain events, or whatnot, the skybox fades through different textures, gradually. Such as, depending on how elevated you are. For example, if I was to keep going up, the skybox would fade to a darker skybox, then eventually to a "Starry" skybox. Another implementation would be cycling for weather changes, or day-to-night, or etc.
Opinions?