Washing your face with cold water has helped me get rid of some acne, though only the acne on my face. I surprisingly have it all over my back.....most likely because I take really hot showers.

The best thing I've ever found is astringent or other salicylic acid based products. It generally comes in 1 or 2% potency and basically eats away at all the oil and dirt on your face without actually harming your skin. It comes in straight liquid which can be applied with cotton balls or in gel form as a face wash. I never wanted to spend the money on something like ProActiv, and this stuff was a miracle worker for me. I recommend it to anyone with acne troubles. It gets the job done without over drying your skin or any weird side effects.

Another trick I grew up using was when I had acne, was put on some regular crest or cascade style toothpaste over the zit (just enough to cover it) and let it dry overnight. It would dry the zit out and be ready to pop first thing the next morning. It doesn't help in preventing acne though, so it has a downside.