Yup vinegar is a good cleaner, it works better if warm, adds its touch, alcohol by itself is pretty strong and can really clean, salt (not much is needed) helps with more of action, and makes the cleaning faster i guess....
... On the other hand you can just use Drano (j/k don't do it...).

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More info on vinegar :
http://frugalliving.about.com/cs/tips/a/vinclean_3.htm
http://www.angelfire.com/cantina/homemaking/vinegar