What's the best accessory on the red carpet? It's not jewelry or a just-right purse; it's the perfect significant other. But where were all the hot dates on Oscar night? It was the rare Hollywood couple who walked down the red carpet together or sat cuddled up in the audience. Some stars stayed solo for the whole night, braving the post-Oscar parties on their own (not that they didn't have fun). Here's a look at the most eligible bachelors and escort-free ladies partying after the big show...