Checking out ebay at the moment, you might have seen the banner advert at the top of the pages for Action Comics #1 (the first comic with Superman, from 1938).
The Auction still has 7 days to go, and is already at US$1.7 million (only pre-approved bidders too, so no fakes)... and is thought to be the best known copy in existence, so could well double that amount. (it looks so clean for a 76 year old comic, as if it was just printed yesterday... but it has been authenticated by a comic grading company that has graded about 60 copies of this comic in their 14 year history)

Aside from the curiosity of how much it ends up selling for (which for comic fans, this will be an historic moment seeing the most expensive comic ever), the auction has some sample pages from the comic, which are an interesting read. (the story is terrible, but I'd never read the first issue before)
Plus, there is a youtube video embedded into the listing that gives a short history of this particular comic, and who the seller is (a comic store owner who bought it 30 years ago).

I wonder if ebay has ever sold anything more expensive than this... which could be why they are promoting it in their top banner (or the seller paid for it). Either way, the sale fee (likely to be about 4% on this one) will earn ebay a lot of money... and a lot more than the charity is getting for their name to help promote the sale (only 1% is going to the Christopher Reeve foundation).