Recreational Sports
UT has a number of IM leagues. These provide a great opportunity to have fun and meet new people. The Website for RecSports has a great deal of information, as well as a sign up schedule for IM leagues: http://www.utrecsports.org/. Since certain sports require that you find a team before you register, you may want to check whether others within the department are interested in creating a team.
[flag football] is the best recreational sport out there. Currently active IM teams within the department: IM Soccer - John Erickson
Another resource specific to Ultimate in the Austin area is http://www.austinultimate.org/.