coffee has more caffeine than red bull
From:
http://www.redbullusa.com/extras/ingredients.jsp
red bull 80mg caffeine
From:
http://www.marchofdimes.com/professionals/681_1148.asp
COFFEE (8-oz. cup)
Brewed, drip method - average 184 - range 96-288
Brewed, percolator - average 128 - range 64-272
Instant - average 104 - range 48-192