Geoff Pullum on the IPA

Studying the full array of symbols (see the definitive one-page copyright-free chart here) reveals that for almost any point in the mouth or throat where an obstruction or radical restriction of the airflow from the lungs can be made by lips or teeth or tongue or pharynx, such a restriction will be used to produce at least some consonants: sounds produced either by complete occlusion of the airflow or by narrowing or interrupting the channel to produce hissing, buzzing, scraping, trilling, rattling, or clicking.And for every reasonable position in which you can hold the tongue and lips and cheeks while permitting unimpeded airflow, there is a vowelsound employing that oral posture.

the whole thing here