I'd have to chip in with the Point Sur nomination. Others on my list:

2. Point Betsie
3. Ontonagon Lighthouse, MI
4. Detour Reef Lighthouse, MI
5. Crisp Point Lighthouse, MI
6. Pigeon Point, CA
7. White River Lighthouse, MI
8. Pottawatomie Lighthouse, WI

I have two more to go...