1a. Re: Closest 50/50 bet in a casino? There might be a good comp play h
One more on this - and I don't even know if it's a game that is available to you for the action you're trying to generate.
Baccarat has been mentioned as having a 0.5% edge. Just like taking both sides of any other bet (that doesn't have a lose-no-matter-which-side option like the zeroes on the roulette wheel), you and a partner can play baccarat, with one of you betting the house and one betting the player. It is a no-skill game, all plays are dictated by the rules.
A friend and I used to do this a LONG time ago when we first went to Vegas; we'd pool the money and share the win/loss, so all we ended up losing was the house percentage, which used to be about 0.5% after the house takes its commission on the side that has the slightly positive EV (I can't even remember which side that is now). We were guaranteed a loss.
At the time we did it, baccarat was a very slow game, and there was $10 minimum available, so we would lose about 5 cents a hand. Drinks were complimentary (for a tip) and our purpose of this "play" was to get drunk on comp'ed drinks at almost no cost -- and to do so at this very serious / stuffy game with tuxedoed dealers and supervisors.
Again, when we were just barely old enough to go to Vegas, this seemed like a good idea 
--BG
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