Oh gosh, what songs have I listened to before that aren't linked to some memory from the past?
On the top of my head, every time I hear "Hollaback Girl" by Gwen Stefani or "Beverly Hills" by Weezer I instantly think back to 2005-06. I was in the eighth grade and was friends with a girl named Sammy, who was a junior in the high school. Coming home with the bus, she would sit in the seat behind me and we would listen to these two songs so much on her MP3 player. We actually became friends because of "Hollaback Girl" when she heard me singing it on the bus.
Another song that brings back pretty distinct memories is "A Thousand Miles" by Vanessa Carlton. It all began with the movie White Chicks when I had watched it with my family ─ my mom, dad, sister, aunt, uncle, and two cousins. Anyway, what makes that song so memorable to me today is that at the time the same family I mentioned would take road trips to visit us to our house up North Florida, since they lived more south and my dad worked down there. It so happened that the song was on a CD we had. So every time it came on, my aunt, my cousins, sister, mom, and I would just be singing it the back of the car and recalling scenes from the movie. It was all very hysterical at the time. It happened so often that I can't not think of that time whenever I hear "A Thousand Miles."
Also, an obvious one, the original Pokémon theme song and the Sailor Moon theme song. Like, what kids growing up in the 90's doesn't have fond memories of those?
There so many more memories I can link with songs, especially more recent ones, but these are what's ringing in my head for now.