I met Chris who invented the handSteady cup. It is a cup with a rotating handle so that it tilts as you move your hand, helping to prevent spills for people with tremors and ataxia. Also makes it easier to drink as you can hold it in different ways.
I’ve reviewed it and some other drinking aids here:
http://livingwithdisability.info/drinking-aids-review-including-handsteady/
You can watch Chris Peacock inventor of handSteady speaking a bit about his new product and explaining how it works here: