The Queen Saovabha Memorial Institute is a genuine scientific institution that happens to have public snake shows.
Run by the Thai Red Cross, the Snake Farm produces anti-venom from snakes it keeps on-site — it's a working medical research facility, not primarily a tourist attraction.
Public snake-handling demonstrations at set times (check schedule) where handlers milk cobras and pythons for venom — educational and legitimately impressive.
The institute supplies anti-venom to hospitals throughout Southeast Asia — the show explains the process; well worth supporting by visiting.
Near Lumphini Park; MRT Si Lom or BTS Sala Daeng; entry 200 THB; shows at 11 AM and 2:30 PM weekdays.