I have a cup-holder on my Wee-Strom. It's nothing fancy, just a stainless steel shell made from a large coffee cup, screwed to a tough plastic clamp for a garden hose. I have a tough zap-strap going around the holder and the left mirror, and my cup stays aboard in all conditions. I grab the mug in my left hand, thumb the lid open if it's closed, and sip my coffee, then close the lid and put the cup back.
I like to ride about 500 miles or 800 kilometers in a day, and I would like the ride much less without coffee at hand.