A quick Javascript tip that I pass along in a lot of code reviews is to make use of an options object as a hash to pass a large number of parameters to a function without writing each one individually. For example:
function doSomething(id, someParameter, anArgument, optionC){ };
vs.
function doSomething(id, options){ };
By encapsulating the 3 additional parameters into an options object and passing them individually, you make for cleaner code.
A quick caveat is to check the options object to ensure that all of the necessary properties exist before running your function.