Common plays the Park at 14th this weekend. The show is free — if you mention the Going Out Guide at the door. (Cass Bird/AP)

And when we can, we try to facilitate great events for you. This weekend, at the Park at 14th, you can see rapper Common for free — gratis, on the house — by simply mentioning the Going Out Guide at the door.

Southwest D.C. is going to be packed with top-tier contemporary art this weekend as part of an arts festival put together by 10 organizations. Chief among the shows is the (e)merge art fair, which brings in works from national and international artists selected by some of the biggest curators and gallery owners in the city. Get a sneak peek here.

The indie counterpoint to (e)merge is in Northwest, where the But Is It Art? Fair will highlight the works of local artists. You can see a preview of it here.

Over on the Mall, some of the biggest names in present day literature will be in town for the National Book Festival, a weekend-long celebration featuring readings, author discussions, writer workshops and more. Scheduled to attend are Dave Eggers, Garrison Keillor, Russell Banks, David McCullough, Toni Morrison, Siddhartha Mukherjee, Jennifer Egan, Amy Chua and others.