One of the original online magazines is for sale. Slate, the web-only mix of politics, news, arts, and humor which was created by Microsoft in 1996, isn’t actually losing money, but in a year in which Microsoft’s MSN business division, which includes Slate, is looking to tighten up operations, the company is listening to offers for the first time. Microsoft is stressing that Slate will continue to be published, regardless of whether a buyer is found, and there will not be a sale just for the sake of a sale.