Travelers checks are similar to money orders, though used by travelers while traveling. They can be cashed at banks and at many hotels, and can be voided if they are stolen.
With the recent Amex promo, you can buy up to $1,000 in checks every two weeks without incurring and cash advance fees. They are better than the coins in the sense that you are not carrying a load of coins to the bank, but the checks will cost you a $5.95 transaction fee.