some strange government(?) saving plan

My friend was phoned the other week, and told about this amazing saving plan from the govt for people living in deprived areas. They reckon that if you save with this account, you'll get the eqiuvalent of 50% of your 'investment' back. She didn't tell them where to go (surprisingly) and is being sent the details via post, but I was wondering idf anyone else has heard of this account, how legit is it, and should she tell them to go away next time. If it's a good one, how do I get to be classed as a deprived area, cos I want a go!!