Arguably one of North Carolina's best kept secrets - Bear Island was once privately owned and then donated to the state. It is only accessible by watercraft and the state runs a ferry from Swansboro to the island on a regular schedule. Swansboro sits on NC Highway 24 between Morehead City and Jacksonville. The ferry (used to be anyway) costs $5.00 for a two way trip and can usually accommodate about twenty people and their stuff (coolers, backpacks, chairs, etc.). If you don't catch the ferry back from the island before their last trip, you're spending the night!
The ferry ride takes about 15 minutes and runs only at high tide. Once you reach the island, it's about a quarter mile walk to the other end of the island facing the ocean. The island is maybe about a mile long and has just about not a damn thing on it other than sand and water. Recently, a wooden walkway with a snack gazebo and bathrooms were built but don't expect anything else.
The best part is that not too many people know about it (although that's changing little by little) so when you get out there, you have a huge swath of sand to claim and still not be near anyone else.
The island does have designated campsites but I've never spent a night. If you want a non-crowded beach, with little amenities, pack a cooler, some chairs, and beach umbrella and catch the ferry. (Just remember, State Park == no booze)
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* Scott may now make comments about catching ferries every Friday night for less than $5.00....perv