.data()

Store arbitrary data associated with the matched elements or return the value at the named data store for the first element in the set of matched elements.

jQuery.uniqueSort()

Sorts an array or an array-like object of DOM elements, in place, with the duplicates removed. Note that this only works on arrays/array-likes of DOM elements, not strings or numbers.

jQuery.grep()

Finds the elements of an array which satisfy a filter function. The original array is not affected.