If you do a search on Google for “Bangkok snake”, most of the top hits are about the anti-venin centre located at the Red Cross hospital on Rama IV Road. I’m going to try to get there tomorrow morning – 70Baht to hold a snake for the first time in my life seems worthwhile.
Do a similar search for “Hanoi snake” and the first page lists places you can go to eat the creatures. Something, incidentally, I do want to try when I’m there.