Most credit card companies give you around 6-9 months interest free if you transfer across to them...BUT will only do this if you transfer a credit card over, not a margin loan or other form of loan.
A way around it would be to take out a cash advance on your current credit card and pay out your margin loan, cop the 20% interest plus 2% fee...and then take out a new credit card with the 9 month interest free. In 9 months, take out another credit card with a 9 month interest free period - and continue the process until you exhaust all credit card companies.