It may sound crazy, but there will be quite a few chances to travel while you are in college, at no cost to you, especially if you are willing to get your hands dirty while you're at it. Many schools offer alternative spring breaks. For example, my school once took interested students to Nashville, TN to volunteer with homeless organizations.
Other campuses groups, such as greek organizations and Student government, send their members to annual conventions. I personally have been to Chattanooga, TN, Philidelphia, and North Carolina for activities conferences, and in a couple of days I am going Birminghan, AL for a sorority convention.
These chances are once in a lifetime. You will not get to have this much fun on a free trip after college, so take advantage of it while you can.