The only (legit) way I know to make money that fast is to sign up for one of those bullshit 'work every day for a few months' labor jobs where they cover your hotel, food and transportation somewhere out-of-state. I know a few dudes who are away doing a three-month tour of storm-ravaged Florida and they'll have around $15,000 banked by the time they get back.
Then again, I dunno how often word of this type of shit spreads out to BX.
And, seriously, fuck going into the military. Some dufus I went to highschool with signed up for the same reasons you mentioned- not having shit to do with his life- and got a hernia while on duty. Which is fine, because hernia's aren't really shit in the grand scheme of things, but the problem came when dude had it operated on and the military doctors clipped when they were supposed to tuck and caused some major nerve damage that he'll be dealing with for the rest of his dufus-ass life.
Compensation: About $1,200 a month for the rest of his life. You know, just enough to pay rent and sit around and drink because even sitting in a classroom for 2 hours has become unbearable.
By the way, I just bought a car... so, like, plan on throwing 40's full of rotweiler piss off your roof come June. I'll scream at ya.