I've seen some neat tinting effects created by intentionally mis-setting your camera's white balance. The camera bases what color everything else is from what color you say is white. If you tell your camera that an orange-ish yellow is "white", all of a sudden, the world seems more blue. close your iris a bit and you've got a nice, dark, underworldly blue scene.
Of course, the downside is that when you film it this way, there's no amount of editing that will make it look completely normal again in post. You can try using Vegas' color correcting filter, and jacking up the reds and yellows, but it won't look quite right.
Give that a shot, and let me know if it's closer.