I recently attended a conference at Moscone and took full advantage of the lists people have compiled in the past - I thought it would be worth it to start a 2013 thread.
In the Westfield Shopping Center:
M.Y. China - tried the wild boar scissor noodles, which I enjoyed because I love carbs. However, if I am to be truly critical, they were a bit sweet and soft for my taste. Decent wok char though.
Cupola - a plate-sized piadina was a satisfying and quick meal. It was quieter and more restful than M.Y. China - I will probably go back here in the future.
In SOMA, within a few blocks of Moscone:
Ruchi - I had the veg thali - it had a pretty good paneer tikka masala, plus rasam, sambar, buttermilk, rice, naan, pickle, and sweet vermicelli dessert. Saravana Bhavan it is not, but it was a nice break from all the Italian food I was eating that week.
Zero Zero - they have a great weekend brunch menu, and very few people at lunchtime on Saturday - I had some very good arancini, followed by biscuits and prosciutto gravy. The biscuits are outstanding.
54 Mint - I had a mediocre Roman-style artichoke (too tough and stringy, and I didn't love the soggy breadcrumbs), and a fantastic spaghetti carbonara. Their guanciale is insanely good - it's fried to the texture of chicharrones, with a crunch and meltaway like Cheetos. I will definitely return for this dish alone.