The Hawaiian Tel Federal Credit Union used to have the word "Employee" in the middle. Not anymore. They are open to anyone living or working on Oahu.
This is a good thing, as it means almost anyone can take advantage of what this credit union has to offer. Savings rates are competitive with other local institutions (but they all pale in comparison to those Internet banks), and you'll have access to the numerous services offered (many without cost) to members such as notary service and traveler's checks.
So don't be fooled by the name...as long as you live on Oahu, you can enjoy the many benefits of membership.