Teechino brand Herbal Coffee makes a great coffee substitute. It's also the best way to wean yourself off coffee! You start out with a small amount of Teechino added to your the ground coffee in your coffee maker and then gradually add more Teechino and less coffee every day. Specific directions on how to do this are on the bag.
Teechino is giving out free samples and you can also add yourself to their newsletter for future promotions and coupons!