pourers - to replace caps on bottles
shaker cups and strainer
fruit - limes for sure, lemons - one or two - for day of event/gathering
fruit juices, tonic, club soda, diet soda and soda
knife and cutting board
blender and ice - if called for
long handled spoon
bev naps and stirrers
bar rags for the host/hostess
specialty glass wear - martini glasses, shot classes, snifters, margarita glasses
on day of social gathering, inquire as to beverage of choice; stock accordingly
I'm sure there is more - it's just been a while.