Cameron Diaz puts on her bikini under a towel wrapped around her waist while on a surfing trip on Oahu with beau Justin Timberlake on Saturday (September 4). The pair spent three weeks total in Hawaii, dividing their time between Maui and Oahu. The surfed, celebrated Diaz’s birthday, relaxed, and went to a spa during their trip. On their last full day in town, the *NSYNC star surfed with pals, while Cameron stayed home at the couple’s rented estate. The John Paul Mitchell compound includes five separate homes and a private beach and rents for upwards for $5000 a night. Check out pictures from TheSun.