So, I went through and tallied up everyone's spell lists - remarkably enough, we've only got 1 duplicate; the ever-popular "Whispers through the Black Gate". And the winner by a country mile in terms of "most popular form" is of course Vim.
Animal
Image of the Beast (InAn 5)
Aquam
Cloak of the Duck's Feathers (ReAq 5)
Comfort of the Drenched Traveler (PeAq 5)
Corpus
Awaken the Slumbering Corpse (ReCo 25)
Charm Against Putrefaction (CrCo 10)
Lifting the Dangling Puppet (ReCo 15)
Revealed Flaws of Mortal Flesh (InCo 10)
Spasms of the Uncontrolled Hand (ReCo 5)
The Chirurgeon's Healing Touch (CrCo 20)
The Inexorable Search (InCo 20)
Whispers Through the Black Gate (InCo 15)
Whispers Through the Black Gate (InCo 15, Me)
Ignem
Palm of Flame (CrIg 5)
Pilum of Fire (CrIg 20)
The Dying Light - (Creo Ig 5)
Winter's Icy Touch (PeIg 10)
Imaginem
Discern the Images of Truth and Falsehood (InIm 20)
Disguise of the Transformed Image (MuIm 15)
Phantasm of the Human Form (sight) (CrIm 30)
Silence of the Smothered Sound (eye) (PeIm 15)
Wizard's Sidestep (ReIm 10)
Veil of Invisibility (PeIm 20)
Summoning the Distant Image (InIm 25)
Mentem
Call to Slumber - (ReMe - 15)
Frosty Breath of the Spoken Lie (InMe 20)
Loss of But a Moment's Memory (PeMe 15)
The Call to Slumber (ReMe 10)
Words of the Unbroken Silence (CrMe 10)
Vim
Aegis of the Hearth (ReVi - 20)
Breath of Mundane Silence (PeVi 15)
Circular Ward Against Demons - (ReVi - 10)
Circular Ward against Dragons (ReVi 25)
Command Airy Spirit of Magic (ReVi 15)
Dragon's Eternal Oblivion (PeVi 10)
Ear of the Maga - (InVi - 10)
Eject Vis - (ReVi - 15)
Erasing the Unholy Name - (PeVi - 5)
Fumigation of the Righteous - (PeVi - 5)
Hear the Witch-Bell Chimes (InVi 35)
Last Resort of the Cornered Maga - (CreoVi - 10)
Maintain the Dying Light - (ReVi - 15)
Mutate the Useless Grog - (CreoVi 10)
Sense of the Lingering Magic (InVi 30)
Summon Airy Spirit of Magic (ReVi 20)
View the Song of Magical Power (InVi 15)