I am planning on doing un-paid research during the month between my graduation and when I start residency. Fourth year med students do have the option to do research electives that you don't get paid for but do get academic credit for. I think that most med students don't get paid for research outside of participating in research programs during the summer of first year (for which you should definitely try to get paid for, as the money is usually available when you are able to work full time for a few months). I have a few classmates that have been doing research projects during the school year, and none of them are getting paid. If you have a good project (ie good clinical relevance with a good chance of being published), I think that outweighs any financial compensation you can hope to get. If you do insist on receiving financial compensation, you can get work-study research jobs, but you will probably be stuck washing beakers or plating cultures or some other menial task. I suspect that most of your med school professors would be turned off if you asked for an hourly wage when they offered you a nice project too. I think that doing research is worth it, it can mean the difference between getting into your top choice residency/fellowship if you are able to publish. Make sure that you really do have free time during the school year if you do research though, you should not participate in research if there is any cost to your grades/studying for the boards, as that is more important then your research.
