I have one of these cards and love it for the free companion airfare benefit. Are there other cards offering the same/similar benefit, or is this the only game in town for someone that doesn't actually fly a lot but appreciates using the benefit once a year (regardless of purchase activity or points accumulation)?

Does anyone know of any referral bonuses if I get my wife to sign up for one too? (We've got 2 kids now so doubling the benefit would be great.)