Be careful with credit cards. If you've gone this long without using them, try not to become dependent on them now!
I use a cash-back American Express card for almost everything I buy anywhere, but it gets paid off in full every month. I also paid off our second mortgage (about $10k) with a Discover card, which has a LIFETIME 0% interest rate (on that transferred balance) as long as I make 2 new purchases a month under the regular interest rate. So I charge $1 in gas, two times a month... in a couple years, that $10k loan will be paid off and will have cost me almost nothing in interest.
Current GMs: '95 Chevy Suburban C2500, '69 Pontiac Executive
Former GMs: '83 Buick Park Ave, '73 Buick Electra, '92 Chevy Caprice 9C1, '98 Pontiac Bonneville SLE, '99 Olds Aurora, '00 Buick LeSabre