He and his wife act as middlemen, matching the person looking for a book with the one who has it for free. Mr Chua says: "It's our way of giving back to the community. We feel there is a demand for a book-exchange service here and we are willing to provide it."
Even though traffic is not high - the website gets about one posting a week - Mr Chua says he and his wife will continue to maintain it. They pay about $80 a year to host it.
He says: "We believe it's for a good cause. You can read more books at no cost. People would want this service if they get to know about it."
•To swop books online, go to booksavenue.co
Share stories and swop books
Ms Xu Ruixin, 28, had always dreamt of starting her own bookshop, but did not have the means to do so. So she decided on the next best thing: to organise book exchanges.
The China-born product manager in an IT company founded Ruxubooks this year, an informal group of readers who meet regularly to swop books and talk about what they read.
The group had its first meet-up in July at Booktique Where Writers Shop, an independent bookshop at Citylink Mall.
Eight adults, including Ms Xu, took along at least one book and sat around a table. They each had some time to say - in Mandarin or English - something about the book they had taken along. This could be interesting facts about the writer, a review of the book or a book recommendation.
One participant recited Lebanese-American writer Khalil Gibran's poem On Joy And Sorrow in Mandarin, from his famous 1923 book of fables called The Prophet.
At the end of the two-hour session, they swopped their books. Participants were left to decide if they wanted their books back. Those who did would exchange contact numbers.
Although the first meeting had no theme, the second one will focus on travel-related literature.
On why she started the book club, Ms Xu, who is single and was born in Jinan in Shandong province, says: "When you own a book, you tend not to treasure it. But when you borrow a book, you tend to treat it more seriously and are more likely to read it."
An avid reader who enjoys Chinese classics and essays, she was also inspired by book-sharing movements in other countries. For instance, people meet and exchange books at "book islands" in Beijing.
The name of the reading group and book swop, Ruxu, comes from a line in the Chinese poem, The Book, by Song-dynasty scholar Zhu Xi.
The poem is frequently quoted to illustrate the fact that if people can be broad-minded enough to tolerate and embrace different ideas, they will always have fresh perspectives.
The next session by Ruxubooks will be held on Jan 7 from 4 to 6pm at the Singapore Botanic Gardens. To sign up, go to www.facebook.com/ruxubooks
The Little Part 1 Cafe in Upper Thomson Road has a bookshelf for customers to pick and choose books to take home.
It used to be filled with books from the three owners' collection when the cafe opened in 2007. It later evolved into an active book-swopping corner where customers can donate books and take some home.
These literary nooks, where people can exchange books with strangers, have sprung up in public places in Singapore. Since 2014, all standalone and regional libraries have book-exchange corners.
In March this year, the Gardens Shop at Tanglin Gate of the Singapore Botanic Gardens started a book bank with 50 books contributed by the shop. They are kept in two bookcases outside the shop's entrance. Visitors can pick up a book or drop one off in exchange for a new title.
Ms Wee Swee Poh, chief executive officer of BP de Silva Holdings, the parent company of Risis, which manages the shop, hopes that the book corner "encourage(s) different families to interact with one another".
"Hopefully, this will help bring back a little of the 'kampung spirit' to the Gardens."
• Gardens Shop@Tanglin Gate, Singapore Botanic Gardens, 1 Cluny Road; tel: 6475-1155; open: 9am to 7pm daily
•Little Part 1 Cafe, 15 Jasmine Road; tel: 6451-7553; open: noon to 10pm (Sundays to Thursdays), noon to midnight (Fridays, Saturdays and eve of public holidays), closed on Mondays and from 3 to 5.30pm on weekday afternoons