DTW (4) - 21R, 21L, 22R, 22L, etc.
DEN (3)
IAD (3)
ORD (3)
DFW (5) - Two pairs of runways close to each other. One other outlier.
LAX (4) - Two pairs of runways close to each other.
ATL (5) - Two pairs of runways close to each other. One other outlier.
28, 27L, 27R, 26L, 26R
Now, which airports have runways that are perpendicular to each other? (90 degrees?)
http://naco.faa.gov/index.asp?xml=naco/online/d_tpp