Scents That Conjure Memories:
1) A certain type of cigar smoke (cheap and sweet, I'd wager). This reminds me of my great-grandfather, whom I called Nonno. He was in his eighties when I was born: an Italian immigrant barber with endless patience for listening to me prattle on. Sometimes I catch a whiff of smoke off an old man and am instantly transported back to a cloudless Autumn day in the mid-70's, walking on a stone wall with my Nonno shuffling along beside me in his bow tie and tweed coat.
2) Lilacs. The house I grew up in had lilac bushes on the property, and to this day lilacs are my favorite flower. When they're in bloom I'm constantly transported back to May days in Massachusetts, playing on my obscenely lush suburban lawn.
3) Onions, garlic, and tomatoes simmering together on a stove. Every other supper of my childhood. The kitchen of my childhood home: wallpaper with strawberries on it, deep sink where I got my hair washed once a week, and a green tile floor.