This presentation has the details about the surface tension of the water

1. Surface Tension

3. Even a piece of steel can do this trick if it is small (steel  ~ 8x water)

12. OK so remember this? (steel  ~ 8x water)

15. Incidentally – Scaling tie-in - Why droplets are droplet-sized - mass increases faster than length or area, so above about 1 cm diameter, water droplet mg >  l, so more likely to get torn apart by its own weight

24. surface adhesion energy

25. surface adhesion energy The water at this surface is at a lower potential energy than the bulk water, so deformations that increase this surface area are favorable and spontaneous