I do wish you luck, but in my experience if you've been impatient in the past, this challenge will last...oooh, 2 days, then you'll deposit and be back to normal. lol.
Plus, counting on freeroll winnings isn't a great idea, they are FAR from guaranteed, and a few losses there, especially when you've gone deep in a game, will send you super tilty.
If you've been used to playing real money
games then I'd be inclined to suggest you deposit $50 (or less...most sites accept $10+ now, including Full Tilt) and play the low stakes instead.
Keep it as a challenge by all means - and post your progress here to give you incentive to stick to stay in your limits!
I just dont think you'll have the patience to grind freerolls to $50 (it could take a year plus! lol). I know i'd get fed up with it. And Tilt run SnG's from $0.30 (daily dollar), MTT's from $0.10 ($1000 rebuy) and tons of micro's. Its not hard to exercise BRM at any level, plus the players you'll be up against will be (marginally) better than the freeroll 'all-in monkeys'.
Best of luck to you, seriously, I just think this one is a bridge too far.