1/2 links seem in these days (3 posts and counting from us); especially on a Vintage Dahons. This bike was spotted by Steve Gluckman, Brand Manager Novara, during a trip to Taipei for the bike show.
Read more about Steve in a MTBR forum from 2002: Bike jockey by design.
Follow us on Twitter
Fan us on Facebook
Suffer Faces on Tumblr
Picking on Mulu
Find us on Instagram
Read us on Android and iOS with the Currents app
Subscribe on Kindle 
Just so you know, this type of chain is known as “pintle chain”, and is most commonly marketed to BMX riders. The selling point is that it is more durable in “grinding” situations, and, of course, the length is more finely tuneable than ti would be with normal style links.
Thank you! Good stuff.