Originally Posted by
aktchi
AFAIK, only zuji.sg offers a meaningful flexible search which is flexible at both ends. For those with only a few days of flexibility, Kayak has a +/- 3 days option at both ends; in my experience it has not been a reliable locator of the cheapest options, but no harm in trying (registration is required to use this feature).
Thanks for the link. I spent some time last night clicking around and it seems very useful, especially if you are very flexible.