ive never had to sign for anything from fedex, and ive had some pretty expensive stuff shipped thru them. ups tho, i always leave them a note and they usually accept that. i wouldve left one for fedex, but i didnt think i was gonna have to sign, haha. oh wells.
signature required is up to the sender, unless the driver doesnt like the neighborhood, then they'll usually require a sig or for someone to be there in person.