because it's through my employer, my APR is currently 0.26% (Fed. Funds Rate + 1bp). With my current balance that works out to abuot $1.50 a month in finance charges.
I get 1% back on purchases, so I funnel all my regular spending through my card and pay off what I spend in a given month.
And on a month-to-month basis, I'm breaking even in terms of cash-flow.