Wow its just lying on the boardwalk! Lucky chap.. of course he could be luckier and actually spot it 'flying' ... (Yups this snake is able to flatten its body and glide through the air!)
"The Paradise Tree Snake is considered by some to be rare, however in Singapore it is commonly encountered in a variety of habitats including mangrove, secondary forest, and parks and gardens. "
p.s. read on the thread about another blog on Singapore Snakes
Snakes of Southeast Asia : Paradise Tree Snake - Chrysopelea paradisi
Flying Snake Home Page by Jake Socha, University of Chicago: frequently asked questions on the species, quick-time video clips of their flight, photos, maps of their distribution, taxonomic details