This is one of the largest music festivals in the nation, 3 days long and held in Grant Park in Chicago. This years official lineup has not been announced, but the rumors so far are Metallica, Red Hot Chili Peppers, The Killers, Beck, Beyonce, Sonic Youth, and Skrillex. Lolla is a very well-run festival with great energy and crowds. There are also after parties that include big/known bands playing small bars all around the city late into the night. I hope fellow Cohorts can make the trip it is worth it!
See for details: http://www.lollapalooza.com/