I never write checks. But I do keep one in my purse just inc case I would need it. Same with stamps - we have some, but everytime I use them I am worried the price went up and I didn't notice :)
The bad part is with a debit card, I normally don't even keep cash on hand anymore. I am more likley to spend it that way also, but when I want to buy girl scout cookies I can't! :)