From the unconventional and awe-inspiring to the hilarious and heartwarming, here's a look at some of the most interesting photos, videos and stories that have our newsroom talking today. What's capturing your attention, filling your inbox and cluttering your Facebook/Twitter feed? Tweet us the stories you're talking about using #InstantIndex or email us at ABC.WorldNews@abc.com and they could appear on World News.

Iran Goes After Argo Iranian officials are so angered at the way the Oscar-winning film "Argo" portrayed their country, they plan to sue its makers, including director Ben Affleck.

'New York State of Mind' Billy Joel was taking questions at Vanderbilt University when a freshman asked whether he could accompany the Piano Man on the stage for a rendition of "New York State of Mind." Joel said "OK" and this magical musical moment was born:

Life on Mars NASA's Curiosity rover, drilling into a rock near its landing site, has found clear evidence that Mars, eons ago, could have supported living microbes.

Mars Curiosity rover in a self portrait from its robot arm. Image: NASA.