Even as online payment biggies are having a field day, thanks to demonetisation , there are a handful of startups that are mixing business and charity to cash in on the cash crunch.Startups like Pastiwala Healthians and Swiggy have stepped up to ease the discomfort around the situation and build their business simultaneously. Agnus Capital-backed Pastiwala.com, a waste-paper collection and recycling startup has been campaigning to provide cash to people in lieu of their waste paper.Since the recycling business involves cash payments, the move can not only help people with liquidity but also bring huge business volumes, according to Paresh Parekh , cofounder, Pastiwala. The firm has seen a three-fold jump in the number of calls received from 325-350 per day to 900-1,500 per day across Vadodara, Surat and Ahmedabad.Ahmedabad-based Poletalks, a community interaction platform that allows people to make or share anonymous comments or information, introduced a new feature ‘utility index’ to indicate any nearby amenities that now includes ATMs with or without cash.In the past one week, the app has garnered 1,500-plus downloads with zero-marketing spend, claims Poletalks. “Reacting to the changing market or especially chaotic sit- uation, can give huge returns,” said Shobhit Gupta, founder, Poletalks.“Even millions in funding could not have helped us in getting such recognition to our business model,” said Satjeet Singh Bedi , founder, BookMyChotu. Started in January 2016, BookMyChotu, an unusual business concept that allows people to hire helpers for small errands — is offering the service to hire helpers to stand at bank and ATM queues after the demonetisation drive was declared.According to Bedi, his chase after investors has ended as the demonetisation drive allowed him to prove his “proof of concept” with real-life case studies and results. Some startups have turned a social experiment into a business model thanks to the prevailing cash-crunch situation.FreshToHome, a marketplace that delivers seafood and meat has started a payment service called IOU (I owe you) as a means of credit for customers, where the customers sign their invoice with a commitment to pay later.“We first offered cheque payment options, but they soon ran out of cheque books. So we started the IOU service as a social experiment, but soon realised that people fulfiled their IOU commitments,” said Shan Kadavil , CEO, FreshToHome adding that it has recovered 20% of its IOUs so far and have witnessed the online payment share rise to 50% of its entire revenue pie with IOUs giving the business a 20-30% growth fillip.Similarly, YouWeCan Ventures- backed Healthians, an aggregator of local pathology labs is providing blood pressure (BP), sugar and BMI (body mass index) test services at selected branches of HDFC Bank, Standard Chartered and ICICI Bank in the Delhi-NCR region. Food-delivery startup Swiggy too has cashed in on the demonetisation drive delivering food to crowds waiting in queues in front of banks.