Trust me on this one.... the best tip you could give is putting their respective name and some positive words on a comment card. You can even go a touch further and ask the employee in question for a comment card and let him/her know you're going to put down what a wonderful job they are doing.

Most GM's or AGM's have an incentive set up for their employees when they get positive remarks on a comment card. Some places give a simple dollar or two, other properties give their employees a lot more.

At the end of the day who doesn't like getting some positive press when it's warranted.... it usually go's alot further then a few bucks.