So I don't really know if this was asked before, but I sure couldn't find it, so at least this’ll make a real nice link straight to the right answer.
I have a pretty simple scene, and right now it looks like crap 'cause I'm not real great at lighting. I was watching a tutorial on the game engine (completely unrelated to my problem) and I noticed that the guy who was making the tutorial had shadows in his game, like full-on-dynamic-wicked-cool-looking-shadows. They didn't seem to be stressing his PC or anything so I thought "hey that's cool" and I tried to make them.
In a book by Mike Pan I saw that only spot-lamps and sun lamps give shadows in the game engine so I switch my Hemi out for a sun and Surprise! it looks worse.
My question after that fantastic monologue: How do I get pretty little shadows to make my game look awesome without weirdo lines streaking through it and messing it up?