July was Amaze a Shopkeeper month.
Here's how it worked if you missed it and want to give it a go:

Find a nice local shop. This won't work at Tesco Superstore, Dixons or any other large corporate outfit. Coventry has a wealth of independent retailers, from corner shops to electrical wholesalers where you can chat to the owner about the price of eggs (particularly good if you went in to buy eggs in the first place!).

Buy what you need to buy. Or if you don't need to buy anything all month then combine it with another act of kindness and buy someone a chocolate bar.

Wait until they tell you how much it is and then reverse haggle them until they give in. Reverse haggling would sound a bit like this (of course, the actual dialogue and amounts are up to you):

shopkeeper: "that's £2 plesase."
you: "how about I give you £2.20?"
shopkeeper: "eh?"
you: "Ok, £2.50 then"
shopkeeper: "what?"
you: (slapping the money down) "you drive a hard bargain mister, £3 it is then!"

Leave a card or explain and then simply walk away and carry on your business.