On a Saturday morning in March, Ms Sonja Piontek and Ms Joanne Flinn challenged themselves to publish Amazon bestsellers in just one week.
Ms Piontek, 43, a motivational speaker and chief executive of luxury travel agency Sonnenkind, had been facing weeks of "practically zero revenue" and wanted to accomplish something inspiring during this downtime.
It was a tight deadline - even for two writers with several non-fiction titles under their belts - but they completed their first drafts within 48 hours. Both Ms Piontek and Ms Flinn, 54, an Australian who is the chief executive officer of business consultancy Unicorning, are based in Singapore.
Their e-books were launched on Amazon just a week after they had started.
Ms Piontek says her book, UltraCreativity - The Experiment, is a kind of testimony.
During her talks, she often refers to "UltraCreativity" as a concept which "unleashes the mind's full potential", through steps like playing to one's existing strengths.
She put this into practice while writing. She says: "I was so familiar with the topic, my greatest challenge was that my fingers just weren't fast enough."
Ms Flinn in turn "distilled" her 30 years of experience in business management into the book Karma: How To Stay Calm And Productive Through Coronavirus To The Recovery. She says the most important thing she learnt was to always practise kindness and hopes to "create some good" with her book.
UltraCreativity has sold just under 400 copies, while Karma has sold more than 150.
Like the duo, many are using the downtime during the coronavirus outbreak to come up with their own books.
In fact, Ms Piontek inspired fellow motivational speaker Uma Rudd Chia to write her own e-book.
In 10 Things Brands Could Do To Survive A Crisis, Mrs Chia, 44, shares insights from her 18 years in branding and advertising.
She completed her draft in just three days, in between juggling a full-time job as the creative director of public relations firm Weber Shandwick and caring for two children aged 11 and nine. Since April 10, she has sold more than 3,000 copies at $1.44 each.
Meanwhile, some parents and educators have published books to help children make sense of the coronavirus outbreak.
One such book, Covid-19 For Kids, is a "family effort" led by Mr Elvin Too, 40, and his wife Catherine Cheung, 39.
Neither have a background in publishing or education - Mr Too works in telecommunications, while Ms Cheung is a management consultant - but they enjoy reading to their children Evan, three, and Claire, 18 months.
Since the end of January, they have spent so much time making up rhymes for the story together, Evan has "pretty much memorised all the words", says the couple.
The book's "colourful and soothing" illustrations are by Britain-based freelance artist Christy Johnson, whom the couple approached on online marketplace Fiverr.
With funding from non-profit organisation The Majurity Trust, Covid-19 For Kids was published early last month.
Though the e-book is free, physical copies are available at $5 each, with all proceeds going to The Courage Fund. To date, they have raised about $2,600.
On May 4, a group of 27 Catholic Junior College alumni published C Is For Coronavirus, an alphabet book to help parents explain unfamiliar words like "isolation" or "asymptomatic".
It retails for $8.57 on Amazon and all proceeds will be donated to six local charities.
For parents with pre-schoolers, local actress Joanne Peh designed a handy guidebook she distributed online in February, via the newsletter of her filmic arts enrichment school The Dimple Loft.
NTUC First Campus' My First Skool also published a free e-book written in English and Chinese, titled Covid-19 - A Child's Voice. It incorporated a catchy tune about handwashing as a "fun way of reinforcing good hygiene practices", says its general manager, Ms Thian Ai Ling, 46, who led the project.
Another three free e-books were recently launched by EtonHouse Community Fund, a non-profit entity set up by EtonHouse International Group.
The first, A New Virus Has Arrived, was released in January and has since been translated into 10 languages, including Malay, Tamil and Hindi. The next two books are about acts of compassion and Singapore's contact-tracing team.
They were written and illustrated by EtonHouse creative and operations manager Amanda Cho, 35, who used rhyme schemes and drawings of familiar places like Housing Board playgrounds and neighbourhood supermarkets.
She says: "We wanted to ensure the content was relatable to children without glossing over important facts."