There are still some lenders out there doing consolidation loans for private student loans, but you will need good credit and income and possibly a co-signer. It's still worth investigating to see if you could get a lower rate.
I also remember reading something on these boards about a program Sallie Mae has for people with a financial hardship to lower their interest rate. I could be entirely making that up, but I'll see if I can find it or hopefully someone else will chime in.
