I use Verizon DSL. Verizon just activated a service that gets their DNS server to lie in response to requests for non-existent domain names. Instead of returning a "domain not found" error, they redirect you to their own search engine, complete with their own ads.
No, thank you, Verizon, I'll take the error message and fix my own typos. Verizon doesn't advertise it, but customers can opt out of this service by visiting this URL: