Make that business travel count!
John Piper's Desiring God ministry is working to alleviate "worldwide theological famine" by putting resources in the hands of national pastors. Shipping is expensive. To get around that, they want to mobilize believers doing international travel to act as theological book couriers.
To join the force, just let Desiring God's International Outreach team know your travel plans. They'll ship you books and instructions. You can read the details here.