Your credit card will be billed at $22.95 weekly and free 3 pack of child porn CD is shipping to your billing address. To cancel your membership and CD pack please email full credit card details to abuse@theplanet.com [...]
The worst part is, I'm sure that there are people out there who will be so flustered by the accusation of child porn that they'll fall for it.
(Although I am surprised and slightly confused that they give an abuse address for an apparently-real ISP as the target to mail to, which may indicate that there's something a tad subtler going on here. It's possible that all of this is an attempt to essentially DDoS the abuse line for the ISP...)