should be a few decent servers up.
there was a online zombie mod server i used to play which was great fun not the normal nazi zombie mod.
Yup zomx it was called, a huge amount of fun, even being the zombie was often fun, providing it wasnt one of those maps where the hunters could hide in a completely safe place, last time I checked server was still up but that was a while back now.
Loved that, shame cod went to s### and removed dedicated servers