Have you ever wondered how fast your ISP really is compared to others? Check out Netflix's ISP Speed Index to find out.
There probably are other sites that offer this information (to be honest I didn't really care to check), but Netflix is one of the few sources I think can give impartial and accurate information.
So if you want to see how well your current ISP rates compared to others. Or, if you're looking to find or change ISPs, I would check out this site.