For http://www.engineyard.com/blog/2010/engine-yard-lucky-13-contest/ - I know it said as fewer lines as possible, but I'm just bored and procrastinating so... enjoy :)

roulette.rb

require 'httparty'
require 'json'

WHEEL_URL = "http://roulette.engineyard.com"
LUCKY_NUMBER = 13 #or not so lucky
PAYOUT_FACTOR = 35

def spin_the_wheel(bet)
  spin = HTTParty.get(WHEEL_URL)
  
  begin #lazyness
    result = JSON.parse(spin.body)
    spin_result = result["winning_number"].to_i
    
    if spin_result and spin_result == LUCKY_NUMBER
      winnings = bet * PAYOUT_FACTOR
      puts "You scored! Winnings: $#{winnings}"
      return winnings
    else
      puts "Winning number was #{spin_result}, you win $0"
      return 0
    end
  rescue
    puts "The roulette wheel jammed up, everyone gets a refund :("
    return bet
  end
end

wallet = 10000
spend = 0
bet = 100
winnings = []

(wallet / bet).times do
  spend += bet
  winnings << spin_the_wheel(bet)
end

total_winnings = winnings.reduce(:+)
puts "In total you won $#{total_winnings} out of the $#{wallet} you bet... you now have $#{(wallet - spend) + total_winnings}"

Ah.... I need to name my methods properly.... odds(bet) should read spin(bet)