Say you make purchases of $X per month x 15 months (october 05 - February 07 plus some leeway). Make the purchases on another card (with rewards) and transfer balances to the Chase VISA. Put the monthly payoff money in an Emigrant Direct 4% savings account; earn [X(1.04)^1.25 +X(1.04)^1.18+X(1.04)^1.08...+ X(1.04)^.08]-[15X] = interest income. Is this arbitrage worth the hassle and potential credit score ding? A crude Excel spreadsheet estimates $797 interest earned if X=$2000, and $1196 earned if X=$3000. I suppose the biggest limit would be one's credit line limit with Chase. Thoughts?