Many of these cards are a friggin' pain in the ass. Most people want to tuck a business card into their wallet/card holder if they're planning to keep it. Otherwise it gets chucked onto my desk, and gradually gets mixed up with other junk before ending up being swept into the bin. Irregular shapes, cords or other attachments etc. are just a nuisance.
Personally I like a nice, crisp, white card from quality stock, with a classic/contemporary layout. Anything more and it gets a moment's extra glance before being forgotten about. I used to get handed so many ridiculous looking cards, I ended up appreciating someone who just gave me something normal. I think the climax of wankiness, was during the first dotcom boom when 'NooMeeja executives' started handing out those little card shaped CDROMs that would run some shitty shockwave movie when you stuck it in your drive. They would just go straight in the trash. Tossers, the lot of 'em.