try blue sky from american express if you fly frequently. you get $100 credit for every 7500 points and $1=1 point. so that means for every $7500 worth of transaction, you get $100 credit if you use your card to purchase flight ticket. this means, you spend $2500 less than chase freedom or most of the other ccs to earn $100 rewards. points never expire, no blackout dates and you can use your points to get credit on any flight tickets, domestic or international. on top of that there's no annual fee.

i always accumulate points and redeem it when i go back to nepal. in two yrs, i earn decent amount of rewards. i've yet to find a better credit card that this one.

goodluck!