Video S1: Condensation on a 40um teflon-coated fiber (Fig. 1): gravity toward right, rf = 40um, field of view = 1143um x 1554um, duration = 30min.

Video S2: Condensation on a 13um teflon-coated fiber (Fig. 1d): gravity toward right, rf = 13um, field of view = 785um x 1068um, duration = 10min.

Video S3: Self-launching upon drop coalescence on a teflon-coated fiber, endview (Fig. 2a): gravity toward right, rd = 249um, rf = 46um, field of view = 1114um x 1406um, duration = 3ms.

Video S4: Self-launching upon drop coalescence on a teflon-coated fiber, sideview (Fig. 2b): gravity toward right, rd = 249um, rf = 46um, field of view = 1113um x 947um, duration = 3ms.

Video S5: Simulated launching process upon coalescence of two liquid cylinders on a fiber (Fig. 3a): contact angle = 120 degrees, rd/rf = 5, Oh = 0.0126, duration T* = 9.

Video S6: Simulated coalescence process of two liquid cylinders on a flat substrate (Fig. 3b): contact angle = 120 degrees, Oh = 0.0126, duration T* = 7.7.

Video S7: Drop coalescence on a flat teflon surface (Fig. S3): gravity toward bottom, rd = 154um, field of view = 752um x 364um, duration = 3ms.

Video S8. Drop coalescence on the same side of a teflon-coated fiber, sideview (Fig. S4): gravity toward left, rd = 275um, rf = 35um, field of view = 1005um x 1213um, duration = 20ms.

Video S9. Wrapping effect of the merged drop around a teflon-coated fiber prior to self-launching, endview (Fig. S6): gravity toward left, rd = 262um, rf = 18um, field of view = 1416um x 1416um, duration = 3.8ms.

Video S10. Asymmetric coalescence on a teflon-coated fiber between drops of unequal radii, endview (Fig. S7): gravity toward right, rd = 507um, rd' = 254um, rf = 39um, field of view = 2111um x 2430um, duration = 6.5ms.

Video S11. Drop coalescence on a polystyrene-coated fiber, endview (Fig. S9): gravity toward left, rd = 360um, rf = 76um, field of view = 1773um x 1710um, duration = 8ms.

Video S12: Self-launching upon drop coalescence on an alkylthiol-coated fiber, endview (Fig. S10): gravity toward right, rd = 238um, rf = 44um, field of view = 1117um x 1011um, duration = 3ms.