Well, not a specific song on a specific day, but LOTS of albums that bring memories from a certain time in my life. Perhaps nothing grand or important, but just memories of a given time. There are tens of those, so I'll fill out at a better time.
December 1997 - February 1998 (when I was 13)
Fear Factory - Carmageddon OST tracks & then Demanufacture
Rammstein - Herzeleid & Sehnsucht
That's when I realised "you can do that too?", that is, combine my two favourite genres, techno & metal
Summer 1998 - Fall 1998 (14)
The Prodigy - Music for the Jilted Generation
Metallica - Entire discography to date (bought them all that summer, one by one)
December 1998 to February 1999 (when I was 14)
Helloween - Better than Raw
Metallica - Garage Inc.
Rob Zombie - Hellbilly Deluxe
Combined with Aliens vs Predator (the PC game)
Summer 1999 (at 15)
Metallica - Garage Inc.
Michael Schenker Group - The Unforgiven
Quake II OST by Sonic Mayhem
Lots of great memories again, also saw Metallica live that summer at Ruisrock
They even played for 2,5 hours.
Fall 1999 - December 1999 (at 15)
Fear Factory - Obsolete
Black Sabbath - We Sold Our Soul for Rock & Roll
Ozzy Osbourne - Tribute
Great times, also saw Black Sabbath live in Helsinki
Summer 2000 (when I was 16)
The Berzerker - S/T
Simply great. I just finished my base school (from ages 7 to 16).
Late 2000 (still 16)
Timo Rautiainen & Trio Niskalaukaus - Itku pitkästä ilosta
Vader - Litany
Waltari - Big Bang
Lots of great times again, however some darkness was brooding ahead.
Spring 2001 (17)
Fear Factory - Digimortal
Opeth - Blackwater Park
Rammstein - Mutter
Lots of great new finds for me, and my current tastes started to form.
Fall 2001 (17)
In Flames - The Tokyo Showdown
Static-X - Machine
Electric Wizard - Dopethrone
Strapping Young Lad - City
Devin Townsend - Infinity
Testament - Demonic
The Project Hate MCMXCIX - Cybersonic Superchrist
More and more stuff, but bad times lurked just behind the corner.
Late 2001 (17)
Soilwork - The Chainheart Machine
That's what I listened to almost exclusively. I lost my school motivation completely, and just never went to school. Just played Diablo 1 all day long and listened to Soilwork. Then I swapped school type entirely...
Late spring & summer 2002 (18)
New, technology-oriented school and brand new motivation. A return to old favourites, and some new ones:
Fear Factory - Demanufacture
Terror 2000 - Slaughterhouse Supremacy
End of 2002 (18)
Lots of gothenburg metal:
Dark Tranquillity - Damage Done
Darkane - Expanding Senses
Construcdead - Repent
Soilwork - A Predator's Portrait
Gardenian - Soulburner
End of 2003 (19)
Dream Theater - Train of Thought
Noise Unit - Decoder & The Drill
Front Line Assembly - FLAvour of the Weak
Cubanate - Cyberia & Barbarossa
Spring 2004 (20)
A big time of brand new musical revelations, lots of current favourites found:
Arcturus - The Sham Mirrors
Emperor - Prometheus
Meshuggah - Destroy Erase Improve
Fear Factory - Archetype
Dan Swanö - Moontower
Joe Satriani - Crystal Planet & Engines of Creation
Jon Spencer Blues Explosion - Mo' Width
Testament - The Gathering
Zyklon - World ov Worms
End of 2004 (20)
Continuation on spring, mostly. Getting the back-catalogues of the new found bands.
Arcturus - La Masquerade Infernale
Ulver - Perdition City
Rammstein - Reise, Reise
Pantera - Cowboys, Vulgar, FBD & Trendkill
Meshuggah - I
King Crimson - Red
Jan & Feb 2005 (20)
Led Zeppelin - I, II, III & IV
Ulver - Lyckantropen Themes & Perdition City
Front Line Assembly - Maniacal (CDS) (if CDs could be physically worn out, this CD wouldn't exist anymore
)
Peccatum - Amor Fati & Lost In Reverie
Spring 2005 (21)
Scar Symmetry - Symmetric In Design
Judas Priest - Angel of Retribution
Soilwork - Stabbing the Drama
King Crimson - In the Court of the Crimson King
Summer 2005 (21)
This is the time when I finally discovered dark ambient & darkwave big time.
Karl Sanders - Saurian Meditation
Ice Ages - This Killing Emptiness & Strike the Ground
Elend - Winds Devouring Men
Dream Theater - Octavarium
Ulver - Blood Inside
Fall / End of 2005 (21)
Now I'm in the army, and thus my musical discoveries slowed down a lot. Mostly buying new albums from old favourites. Another wave of dark ambient/darkwave.
Arcturus - Sideshow Symphonies
Evergrey - In Search of Truth
Noise Unit - Voyeur
Amorphis - Eclipse
Samael - Reign of Light
Mayhem - De Mysteriis Dom Sathanas
Delerium - Spiritual Archives
The Amenta - Occasus
The Kovenant - Nexus Polaris
Dargaard - In Nomine Aeternitatis
Early 2006 (21)
Army service is done, and my 8 months' (!) summer vacation started. And I even got 188 euros per month from the state, to fund my music purchases
LOTS of Evergrey (all their stuff in fact)
Devin Townsend - Synchestra
Coroner - Mental Vortex
Kyuss - Welcome to Sky Valley
Sephiroth - Draconian Poetry & Cathedron
Spring 2006 (22)
Continuing my vacation
some more stuff again. The Elder Scrolls IV: Oblivion was a very very integral part of this time period.
Centinex - Decadence
The Haunted - rEVOLVEr
Satyricon - Now, Diabolical
Scar Symmetry - Pitch Black Progress
Ministry - Rio Grande Blood
Dead Can Dance - Within the Realm of a Dying Sun & The Serpent's Egg
Summer 2006 (22)
My all-time favourite summer. Lots of football (soccer) and music, plus cruising around in a new car with a CD player!
Still lots of Oblivion.
Front Line Assembly - Artificial Soldier
Raison D'être - The Empty Hollow Unfolds
Textures - Polars
Stam1na - S/T
Nile - In Their Darkened Shrines & Annihilation of the Wicked
Cannibal Corpse - The Wretched Spawn
Metsatöll - Hiiekoda & Terast mis hangund me hinge
Late summer 2006 (22)
Celtic Frost - Monotheist
Keep of Kalessin - Armada
Bloodbath - Nightmares Made Flesh
Necrophagist - Epitaph
Right now, end of 2006 (22)
Unexpect - In a Flesh Aquarium
Amon Amarth - With Oden On Our Side
Rammstein - Völkerball
Now
THAT should do it, no?