A good fry-up and gallons of tea usually sort out any signs of over-indulgence for me.
Although a friend gave me a very handy hint for not getting a hangover to begin with, which is to have something salty like a packet of crisps and something sweet like a piece of cake washed down with a large glass of water before bedtime. Sounds daft, but it works. I think it's something to do with replacing the electrolyte thingies as well as the fluid lost. A bit like the sugar-saline solutions they give people who are dehydrated.
Of course, you need to be able to co-ordinate sufficiently to cut a slice of cake and open a packet of crisps.....