I've had great experiences lately. Chili's to go gave me a near empty chili, posted a pic on FB and ended up with a gift card (they showed me all food there except the chili for some reason, and I didn't question it).
Verizon has called me up before to see if they can get my bill down.
Cox (cable) has been willing to get me deals that bring my bill down as well.
I don't threaten to cancel, just say it like it is when it's too expensive.