I published a couple things for Kindle and I am working on more. I found somewhere to get free business cards and thought I might as well do that soon, but I'm not even sure they'd come in handy. If you have business cards, have they helped you make connections or get attention? Where do you pass them out? edit: Maybe this should have gone in the general chat forum. Sorry.
I have found private business cards to be mostly useless. I don't bother with them any more. My home address also seems to change so rapidly that I can never use more than ten or so cards before I need to order new ones. At one point I had four business cards, three from different companies I was working for and one private. Since all of them had my mobile number and an email address that I was checking regularly, it didn't really matter which one I handed out.
yes sorry, didn't make that clear. If there is a chance that one day you may be in a situation where you need one and they are free to have, then you may as well have them, just in case. besides, imagine if you didn't get them and you later found that you needed one, you'd kick your self it usually only takes a minute or two to fill in the details you need these free websites. so what have you lost.
Instead of a "business card", why not have calling cards? No matter the circumstance, you have a card with your name, phone number, and email address = those details that normally stay constant. Now you have cards to hand out to business associates, potential agents (or other similar networking persons), new acquaintances, etc etc. = any time you find yourself trying to find a scrap paper or napkin to jot down your contact details for someone.
I have found them handy for book signings and events (cons and such) where I meet both readers and other authors. I designed my own. Check the local vocational school if there is one near you, and if they have a graphic arts/design program, they may be willing to design/make some for you basically at cost of materials. With e-books (mainly Kindle as you indicated) and if you're not going to interact in person with other authors, ediors, and/or the public, then they may not be as needed. Two dozen may last you a year or more.