Source: http://en.wikipedia.org/wiki/Friction_coefficient#Coefficient_of_friction

Materials		Static friction, $\mu_s\,$
Materials		Dry and clean	Lubricated
Aluminium	Steel	0.61
Copper	Steel	0.53
Brass	Steel	0.51
Cast iron	Copper	1.05
Cast iron	Zinc	0.85
Concrete	Rubber	1.0	0.30
Concrete	Wood	0.62
Copper	Glass	0.68
Glass	Glass	0.94
Metal	Wood	0.4	0.2
Polyethene	Steel	0.2	0.2
Steel	Steel	0.80	0.16
Steel	PTFE (Teflon)	0.04	0.04
PTFE (Teflon)	PTFE (Teflon)	0.04	0.04
Wood	Wood	0.35	0.2