Canon Pro 90 IS, tripod.
+4 Diopter.
Canon 380EX flash, bounced off white wall and yellow detergent bottle with red cap.
Subject is 2-liter soda bottle, inverted with hole in cap, water (with a touch of soap) stirred to induce whirlpool while draining.

Biggest pain in the ass was trying to keep outside of bottle clear of water drops.