We study the dispersion relation for scalar excitations in supersymmetric,
non-commutative theories at finite temperature. In N = 4 Yang-Mills the low
momentum modes have superluminous group velocity. In the massless Wess-Zum
ino model the minimum of the dispersion relation is at non zero momentum fo
r temperatures above T-0 approximate to (g theta) (-1/2). We briefly commen
t on N = 2 Yang-Mills at finite density.