This offer is only for those with a Kindle with Special Offers:
Save 50% on a Kindle power adapter & USB cable at Amazon.com
Click on offer, then click on the link on the offer page to receive an email with the promotion code. Sign-up for this offer expires on September 29.
You'll get an email (right away), a link to the Special Offer page and a promotion code to enter at checkout. Once you have the promotional code, you have until October 29 to complete your purchase. Like previous offers, this one requires you to use the full checkout process in order to enter your promotional code. Also, like all Amazon sales that use promotional codes, if you have a gift card balance, you must use it for the payment (if there is not a sufficient balance, then you can pick which credit card or other payment to use).
Limit one offer per customer and per device.
Lamest deal ever? I had one cable to bad - Amazon replaced it free. I get a new power adapter with each Kindle (and many other devices) and those who buy a overseas Kindle can order one at half-price with their Kindles (specific to their country). Might be useful for that used Kindle you bought from someone who "lost" their adapter (except we all know those are most likely stolen Kindles and can't be registered with Amazon, although I suppose they work ok for DRM-free books). Presumably, since you have a KSO, you have at least one of these already, so the only use I can see for it, is if you want to have a plug in at work (and don't have a computer there, with a USB cable to attach to it).