Hitman: Blood Money Easter Egg - Mexican Wave

In the level "A New Life", you can get the guards to celebrate the wife getting killed.

First, you need to get the pool boy outfit. Then go up to the target's wife, and she'll have you follow her up to her room. When you get there, she'll say a few things, then eventually fall asleep. Steal her necklace. *This is important. If you don't steal her necklace first, the egg won't work.*

Then, you need to get BOTH bottles of lighter fluid. One is in the pool shed, the other is in the basement.

Once you have these, go to the BBQ by the pool, and the option "Rig the Barbeque" will appear. Select it. 47 will then pour ligher fluid on the BBQ.

Now just wait. The wife will come back downstairs and use the BBQ, at which point there will be an explosion and she'll burst into flames. Normally, the guards all rush over to help, but this time, they'll all line up and start clapping, then they'll do "the wave".