They work! I had ordered the Zero Limits III DVDs and they all worked except one. It would not play on my DVD player, nor would it play on my computer. So, I put a Ceeport sticker on it and left it there for a week, and then tried it again a few nights ago. It worked like a charm! Ceeport stickers, cards and pins work to clean whatever you put them on. I have a sticker on my cell phone, I use the Ceeport bookmark to clean whatever I'm currently reading, and I wear the Ceeport pin constantly.
Here's the link if you're interested in finding out where to get Ceeport items (I have no affiliation with them). http://ihhl-ceeport.com/shop/