Lighting Shabbat candles with my mother.
My family has used the same set of candlesticks since before I can remember. To me, lighting the candles on Shabbat is about familiarity and tradition. My mother likes to tell of her grandmother (my great grandmother) doing the same thing, and how she brought Shabbat observence with her from Russia, where her grandparents took part in the same weekly ceremony. I really like the idea that I'm helping to continue a tradition that stretches back through so many generations of my family.