Don't do it just for your resume...but if you have sincere interest in serving underserved people, then do it.
I spent a summer in Thailand as an ESL math teacher, and spent some time in a med clinic and AIDS orphanges and my interviewers really liked seeing my international serivce interest.
The experience will look great on a resume and can be life changing (worth $1,800), but if you get into interviews and aren't passionate during questions about the experience, it doesn't help you at all.
personally, I think you should go for it!