Kelloggs has opened what it claims to be the world's first "Tweet Shop". To launch its new savoury Special K Cracker Crisps, the cereal manufacturer is offering Londoners the chance to pop into a dedicated Soho store and pay for their snacks using Twitter postings as currency.

The shop on Meard Street in central London will be open from 9am to 5pm until Friday 28 September, and also offers a "try before you buy" snacking area and "community noticeboard" - a tweet wall, basically - that gives shoppers a live view on the social media reaction to the shop and crisps.

Red dress-wearing Special K shop assistants will be on hand to help customers, and Londoner Kim Murray was the first to try out the service this morning (Tuesday 25 September).

Sarah Case from Special K explained that the Tweet Shop is a direct response to the fact that social networking is rapidly becoming a hugely important way of getting a product message across to the mass market. "The value of positive endorsements on social media sites is beyond compare so we’re excited to be the first company to literally use social currency instead of financial currency to launch this new product in our bespoke Special K shop," she said.

"This is big news for Special K and we are hoping the brand’s move into crisps and the high street will create a major buzz on and offline."

Special K Cracker Crisps come in sea salt and balsamic vinegar, sweet chilli or sour cream and onion flavours. Each pack contains under 100 calories.