I gave reuseable cups in party favor bags (that I cleverly named "Swag Bags") and cut flags like this that said "Thanks for attending Kelli's Bachelorette Party! See you on 10/20!" It added that personal touch!
Teacher's Appreciation handprint flower card. At Montessori they are with their teachers for three years. I'd like to try to remember to do a handprint each year, then give this as a gift at the end of the third year.