What can be done to help neck cramps?

Heat, stretches. Heat (can microwave some rice in a sock for a cheap heat pack), and gentle stretching. Massage also helps. Also, make sure you stay hydrated and watch your posture. Having a poor posture especially while sitting or working on a computer can predispose you to neck pain.
Spasms. Spasms usually respond well to things like moist heat, massage, and/or the use of muscle relaxers. If they persist, it suggests something underlying like a pinched nerve that is causing them.