I think I lost $10 in playing slot machines in a casino. For me that's pretty big because I don't gamble that much.
Losing on gambling really sucks, especially when you can't afford to lose that amount. Personally I've experience that, losing what I can't afford to lose (around 1 BTC) , and its indeed devastating. I feel numb when I saw my balance. I really hate that dice site where I lose my coins (though I know its my fault for being greedy Cheesy ) Anyways I already learned from my mistake, I'm still gambling but I know my limits now.