MUMBAI: The combative lady who runs Kolkata has slammed Narendra Modi 's surgical monetary strike, but her city of joy has come handy to many money bags of Mumbai and Delhi in the past 24 hours.Some of them, desperate to palm off undisclosed cash, have sought the services of several Kolkata outfits to launder money – deploying one of the oldest tricks in accounting and transaction to convert black money into white.It's a simple game where seasoned chartered accountants and money market brokers bring together two kinds of people: one, with excess, unexplained cash and the other having a shortage of it.The Kolkata entities belong to the latter group. These are small firms whose books show large 'cash on hand' but actually hold very little physical cash. These are companies which have spent their earnings and fund withdrawals from banks for personal uses, bribes, and commissions – expenses that are not reflected in their books of accounts. Though their books show 'cash in hand' they don’t really have the cash as it has been used in activities that is difficult to account for.They are the perfect match for people and businesses who are looking for avenues to salvage their hidden bills of 500 and 1000.Here's how it works:Step 1: One looking to offload cash – let's call it M (the Mumbai firm) -- gives the money to K (the Kolkata outfit with cash-deficit). K deposits the money in its bank account. No questions are asked as it had earlier withdrawn cash from the bank or generated legitimate income.Step 2: K issues a cheque in favour of M; in their books the fund transfer is shown as loan or may be advance against a property deal.Step 3: Make no mistake – it’s a loan that has to be repaid. And the understanding is that it would be paid back after a decent interval. The repayment happens with M writing a cheque to K. The `loan principal’ is `repaid’ along with the charge on services that K provides.Step 4: The transaction is complete when K simultaneously returns cash to M. May be this last leg of the transaction (in which K gives back cash to M) will be with the new 2000 rupee currency notes that government has printed.If the stakes are high, a few companies with sizeable 'cash on hand' in their balance-sheets, may even be acquired by those with large undeclared funds.Such deals, say men familiar with the chicanery, would go on till December 31 – the dead line for exchanging and depositing 500 and 1000-rupee notes with banks. According to them, the cash economy has indeed suffered a severe jolt, but it’s unlikely to die in a hurry. Generation of black money will slow down due to an underlying fear of similar ban of high denomination currency bills in future, but most businessmen will continue to need cash to run their shops and search ways to create it.The road to a cash-less system could be long and tortuous.