Stolen from scarydan (from here):
…here is a list of my top 25 played songs… but only one from each artist.
Opeth – Deliverance
Deathspell Omega – First Prayer
Forest of Shadows – Sleeping Death
Meshuggah – Concatenation
Nile – Sarcophagus
Slayer – Stain of Mind
Metallica – Master of Puppets
Lacuna Coil – Unspoken
Astriaal – Renascent Misanthropy
Emperor – An Elegy of Icaros
Anorexia Nervosa – The Shining
Dimmu Borgir – Burn in Hell
Iced Earth – Hallowed By Thy Name
Mourning Beloveth – The Apocalypse Machine
AC/DC – Thunderstruck
Fear Factory – Demanufacture
Gehenna – Lord of Flies
Marilyn Manson – The Fight Song
Secrets of the Moon – Miasma
Mandrake – Crowned With Leaves
Devin Townsend – Christeen
Forgotten Tomb – Todestrieb
Testament – D.N.R.
Tool – Schism
Tristania – Beyond the Veil
I should also point out that this is coming up for seven years worth of music and playcounts! I started using iTunes full-time when the Mac OS X-native version 3.0 came out (September 18, 2002 or thereabouts, according to Wikipedia).