I have a few more points about graduate school and personal finance. (Why isn't this sort of thing covered by graduate schools? I mean, you'd think it wouldn't be that hard for someone to come up with a glossy one-pager that would help out the students that are going to be populating your halls for the next 5 years...)
The taxman interfereth: An astute commenter (Anon709p) notes that, if you're being paid by a graduate student stipend (rather than a salary), you are not allowed to contribute to an IRA. (IRAs are meant for people who have taxable income.) The law around this is a little complex, but a good indication is that if you're not paying FICA taxes, you can't use those funds to fund an IRA. Doesn't mean that you can't save that money up, which brings me to my next point...
An emergency fund: Starting out in graduate school? First time that you're making your own money? You should probably save up an emergency fund of some sort. A good rule of thumb is that it should be about 2 to 3 months' worth of expenses (rent, groceries, gas, car insurance, etc.) Remember, it's an emergency fund, not a fund for quick vacations to Panama City.
Credit cards = mostly bad news: If there's anything to be learned from the last 3 years, it's that credit cards and other forms of consumer credit can be really, really harmful to your medium-term and long-term plans. I'm not saying that you should cut up your awesome American flag Discover card, I'm just saying that running a balance will cost you. But you knew that already, right?
Student loans -- what are they good for?: Should you get a student loan? That's a really tough question, balancing your long-term employability and financial goals against short-term quality of life.
If it's genuinely going to increase your quality of life (e.g. you really like your sleep, so you don't want a roommate), it might be worth it. But if you're taking a student loan so you can afford short-term consumption (dinners out, spring break in the Outer Banks, microbrew sixers instead of Natty Ice), this is a bad idea. If you get a postdoc, you will be on the hook to pay that loan back six months after you graduate -- and you know how lucrative those postdocs are. Don't forget, student loans obligation are darn near impossible to escape, even in bankruptcy. Treat them like thionyl chloride -- useful, but dangerous.