One in every 2 million lobsters are blue, one in every 30 million are yellow and your chances of seeing a white lobster are one in 100 million.
Lobsters tend to be greenish blue to blackish brown, much like this one painted by Geoff.
Fun Fact: Contrary to popular belief, lobsters do not mate for life. They do have a monogamous bond, but it only lasts for a couple of weeks. As it happens, male lobsters in particular are rather promiscuous. Cheeky little fellas.