Legit call - when you call JULIE (in IL at least) they have to verify buried gas, water, phone, electric, internet and cable lines before you can do any sort of digging/excavation project. After all - nothing says 'Welcome to the neighborhood' like severing your neighbors internet connection...
Got part of a voicemail that said: "To receive this information again, press one". Message was cut off after that. Received this call twice in 24 hours.