Lawyer with student loans here. At one point I had run some numbers on my loans, and figured out that the majority of the interest paid accrued in the first three years. Once you get to year four, it is a wash, and after year five, you're paying mostly principal (if you haven't refinanced to a 30 year note). I attacked all I could for the first two years as I had not consolidated and was able to take off the higher loans. After three years I was rid of a good amount of the bad loans, and was approaching the "break even point." I paid off one more, and then saved enough to start paying off the rest. However, by the time I got there, I noticed that the interest on those payments was nominal (at least relatively speaking) and I had passed the point where paying off the loan amount was better than investing. So I maxed 401ks and began working it ignore that debt, hard as it may be.
It is still there, and I hate it, but paying it off to be at zero debt now in the long run no longer makes sense to me. I instead am approaching life as "Lets save as much as I can for the next six years, when the debt is paid off, and I'll have a large bump in salary and decrease in expenses when it is over."
The Mint "Goals" feature for paying off student loans was very helpful for me on this--it lets you know how much interest you'd be saving over the course of your repayment.
This may not be mathematically correct, but it is the thinking I have used.