Course rep/Postgraduate research rep are quite boring terms for what is actually one of the most interesting things you can do at University. Here's why:
1) You get to meet, talk to and rant with every single person you represent. Be that your Masters course mates, students in your research group or students across your school. In order to do your job properly you need to gauge the views of those you represent: what they are happy with, what is frustrating them and how they would like things to change.
2) It's a direct line to the people with the power to change things. You will have regular meetings with the academics from your school/faculty to feedback the thoughts of your representees, and they have to listen to you! The University acknowledges these meetings as key to their improvement of the student experience.
3) It's a fascinating insight into University politics. I'm a policy student and a bit of a policy geek, but for me the main reason being a rep is an exciting prospect is that you get an insider's view into the decision making process in the monolith that is the University of Bristol. If you're in any way interested in change-making processes, I would really recommend putting your name forward.
It would be a bit of a mouthful for me to say 'run to be a change-making-policy-insider-democratic-force-for-good-socialite', so: why not run to be a course rep?