Someone who tries to be both part of an anti-social subculture (see punk for a good example) and a Christian, not realizing that you can't support the ideals used in punk and be a Jesus follower at the same time.
I'm very punk, but I can't have sex, do drugs, or listen to any rock n' roll music that doesn't praise the Lord because I'm a Jesus freak.
When someone is done smoking a cigarette, they toss the still lit butt at you, thus the "shooting star" effect. The usual aim for this is to either burn a hole in your clothes or have it go down your shirt without you noticing. Usually, unless they're real bastards, they will shout "shooting star" to give you a warning about what they're about to do.
Johnathan gave me a shooting star yesterday, effectively burning a hole in my new trench coat. He's fucking going down.