I am biased since I worked at KineticaDB, but the KineticaDB t-shirts were the best swag I've ever received. I have a closet full of them, 3x/yr across the three years I was there. I wore some socially and fashionably, and others at the gym. They used high-end fabrics comfortable for day and night.

I think about ROI on marketing and this must be incredible w/r/t Employee alignment. Imagine having employees wear your brand day in day out!