there is a $7,500 first time home buyer tax credit from the gov't, if you buy a house before 6/30/2009. (the bill is currently in congress, it was a interest free loan, they want to make it free money).
Even after the grace period, interest on student loan are tax deductible. there are no reason to pay it off anytime sooner than you have to except for the peace of mind. of course, remember that money paying off a loan can be invest in elsewhere.