What are the best supermarket/retail baby clubs to join for freebies?

[whysoserious]

Can anyone recommend any to join for free nappies/ changing bags etc etc.

Quite willing to hand over address and get bombarded with promotional crap for the rest of my life in exchange for some free stuff. I have no shame ;-)

Boots do a changing bag. Lots of discount vouchers etc but they are more expensive to start with.

Sainsburys give you a newborn bundle with their little ones club. You need to buy a pack of nappies to get it. Items vary but I think mine had wipes, change mat. nappy rash cream and a few other bits.

Boots also give you a voucher for a free bottle or breast shells which is well worth it.