Some libraries, including Cincinnati, will let you use it from home. All you have to do is punch in your card number and pin. It doesn't look like Multnomah will let you do this (I assume that is your library), but you probably know someone in Cinci who will share their card.
On a side note, the director of the library I work for was ranting about Multnomah's inflated circulation statistics a while back. They consistently have the highest circulation for libraries of that size in the country. He seems to think there is some shenanigans.