I sometimes do what I call the TV Remote game. Keep in mind that not every game will work in every wedding. Props for this game will be two poles (painted dowels work well), two rolls of toilet paper (single ply works best and is usually cheaper), and two chairs on the dancefloor, back-to-back.
I usually do this right before the cake cutting, which on the West Coast usually happens after the toasts and before the cake cutting. Before the cake cutting, I will say something like, "Before we get going on the rest of evening, we need to answer that age-old question of, who gets control of this (I then pull out a TV remote out of my pocket), the TV remote." This will get various amounts of laughter. I invite the couple to the dancefloor and have them take a seat in the chairs. Then, I invite the Best Man and Maid of Honor up - Best Man to stand in front of the Groom and the Maid of Honor to stand in front of the Bride. I have my assistant to bring up the two poles and rolls of toilet paper, giving them to the Best Man and Maid of Honor.
I explain that when the music starts, it is the job of the Bride and Groom to start removing the toilet paper from the roll. The first one to do so will have control of the remote for the first six months of marriage. I will then play something like, "Theme from Peter Gunn." I always encourage the guests to root for their favorite. Many times, if the groom is a macho type, he will try rip the paper from the roll. This never works. Anyway, when the winner is declared, I have them stand up and present them with a framed certificate that claims that they have control of the remote for six months, signed by the Best Man and Maid of Honor sometime during dinner.
It works best if the Best Man and Maid of Honor know what will happen, but I never tell the Bride and Groom exactly what is going to happen. I do let them know at the planning meeting that we will be doing something for the control of the TV remote, just not any specifics. Of course, only do this if they want this type of thing - some prefer not to do any games. I know some of you are thinking that this may be a bit over the line when it comes to weddings, but I have always had great responses when I do do it. This also lets the guests know that the party is just starting.
If you aren't comfortable doing something like this, don't do it. Guests can smell fear.