Also a rather risky drinking game using the ingredients listed above.
How to play:
The players sit opposite each other at a table. A pint or half (if you're wimps) is placed in the middle of the table, nearly full. An empty shot glass is floated in the beer (one with a heavy bottom works well, or else put a little schnapps in it to weight it down). The players then take turns adding schnapps to the glass until it sinks. The player who added the last schnapps and caused the shot to sink then has the honour of drinking the whole lot in one go.
Depth charges can be varied by simply changing the type of liquor being dropped into the beer. Guinness and vodka? Delicious!