anybody used business cards for referrals?

[selerson]

I have a friend who is making up 250 business cards for me with my referral link on it. I have started doing some ebay selling and also have a website that I trade envelopes full of coupons that I send out 2-3 days a week so I figure I can slip the card in with the coupons and hopefully I can get at least one out of ten to try it. Has anyone tried doing this? Did it work? I'm also having a garage sale soon and will take the cards and maybe make a flier too that way I can explain it to people in person.