Gosh, loads.
Could do the ALW ones.
Joseph - About half of it. King Of My Heart for the 00s version.
JCS - Could We Start Again Please (well, added for the stage version I guess)
Evita - You Must Love Me
Cats - The various Italian things that replaced Ballad Of Billy McCaw.
Song and Dance - Unexpected Song (though melody was already there)
Starlight - Make Up My Heart, Crazy, Next Time You Fall In Love, I Do, Whole Lotta Locomotion, I Got Me, Megamix (deffo the ALW show with the most new songs).
Sunset - many interlinking sections
By Jeeves - About half of it compared to Jeeves
Whistle Down The Wind - The Gang
Beautiful Game - Boys In The Photograph
Tell Me On A Sunday - Multiple, for the DVO version.
Wizard of Oz - 5 new ALW songs
Love Never Dies - new melody to verses in Beauty Underneath (and lots of re-ordering of stuff)
Phantom stage show, Aspects, Woman In White, School of Rock have yet (I think) to get a new song!
There are also loads of songs removed and general re-writing.
"Musicals aren't written, they are re-written" as they always say.
A couple of other from faves of mine.
Miss Saigon - Maybe (God I wish they'd put It's Her Or Me back in).
Chess - Someone Else's Story. Then that Act 2 opener that Burke sang at the ENO.