Yeap. Exactly why it makes sense to buy the 3G iPad..
Verizon doesn't require a contract. You can pay as you go either daily, weekly, or monthly.
http://www.verizonwireless.com/b2c/mobilebroadband/?page=plans
Another option is Virgin Mobile USB data card + CradlePoint. Virgin mobile also overs pay as you go plans but their cover area sucks.