So technically this is only available to PopCap newsletter 'subscribers', but I really don't see anything wrong in passing this along. If any mod thinks otherwise, please feel free to remove this thread.
Anyway, PopCap is giving away the original Zuma through the 29th. It may be showing its age, but it's still a very fun arcade puzzler. As much as I like Zuma's Revenge, there's just something about its predecessor that makes me come back to it more often than the former.