You have two issues here:
1) The bankruptcy - that's the more important issue
2) If the loan still exists, it is in default so what can Sallie Mae do?
To answer the first question, it depends on when you filed your bankruptcy. If you filed before 2005, your private student loan might have been discharged. If you filed after 2005 (October) then your private student loan was probably not discharged. Easiest way to find out, call your bankruptcy attorney!
I'm going to guess it was not discharged. If it was, Sallie Mae has a problem on their hands. So, assuming it was not discharged and you are now in default, what do you need to worry about? Actually, you're fairly well protected. A private student loan is much like a credit card debt when it comes to enforcement. Whatever a credit card could do in your state is just what Sallie Mae could. What it CANNOT do is take your taxes, just like a credit card company cannot take your taxes. Sallie Mae would first have to sue you to enforce the debt. Then it can probably garnish your wages (you're unemployed so no worries) and maybe they can put a lien on your home, but again, talk to a local attorney for specifics. More importantly, find out how often Sallie Mae sues for default private loans...you might be surprised at your odds of not being sued.
Find a consumer attorney at the National Association of Consumer Advocates at www.NACA.net.
If you private loan was guaranteed by the federal government, the a default can result in your tax refund (including credits), being offset to pay you student loan debt. You will know whether you loan falls into this category because you will have received notices from either Sallie Mae and or from Financial Managment Services, a division of the Treasury Department.
Having your refund taken can be very difficult for families. To avoid the offset, contact the agency and work out a payment plan or request a deferral based on you financial circumstances. Often the agency will work with you.