It's Dial soap. There's a bite missing from the corner. And the seller recommends Boonesfarm Strawberry wine to go with it.

There's only been one bid so far and that was only for one penny. There have been 37 viewers.
Link:
Weird Auction.
Update: I guess having a clean mouth isn't as popular as it used to be. This bar of soap sold for six cents. There are 259 page views.
Despite there being only one brain in the picture, this deal is for two brains. They are human, slightly used. The bodies that go with them (still living, I presume) are available but not necessarily included in this weird eBay listing.

This one started at $1.00 and has gone up to $1600.00 with only four bids. There have been 346 page views.
Link:
Weird Auction.
Update: This weird eBay listing got removed from eBay. I suppose that eBay felt that the seller might actually need his/her brain some day.