Unless you did Verdi (in which case, damn, where’d you go to high school?), I don’t thing MacBeth would be musical theatre.
These are really fun. Here’s mine:
The Fantasticks: Mortimer, The Man Who Dies
Drood: Neville Landless
Titanic: The Musical: J. Rogers
Little Shop of Horrors: Audrey II - Manipulation (god, that rocked)
A Funny Thing Happened on the Way to the Forum: Hero
The Rocky Horror Show: Riff Raff
Honk!: Drake
Fiddler on the Roof: Mendel
The Music Man: Charlie Cowell
Into the Woods: Narrator / Mysterious Man
Bat Boy: Doctor Parker
Cats: Old Deuteronomy
I have also directed: Little Shop of Horrors (different production), The Secret Garden (twice), For the Glory: The Civil War Musical, Jekyll & Hyde, The Scarlet Pimpernel, Once on This Island, Aida, Oliver!, The Baker’s Wife, Godspell, Dracula: The Musical, The Last Five Years, The Who’s Tommy, and, this fall, Beauty and the Beast and Elegies.
storyteller, musical theatre nerd since 1996
I was usually in the pit (violin/viola) or in non-musical plays. But I actually had one singing part:
Jud in *Oklahoma! *(as in “Pore Jud is Daid”).
I also played Allesandro in *Ramona. *Though it’s not a musical, I did have to enter singing a couple times.
Pit orchestra conductor: Pippin
Pit orchestra bassoonist: Jesus Christ Superstar, A Chorus Line
(The above were college productions.)
Enthusiastic singer-along-to-soundtrack-in-car: Too many to mention
shit shit shit
Wait!
I turned pages for the pianist during a summer production of The Fantasticks!
(I’ll get in on this yet!)
Anything Goes - Sir Evelyn Oakleigh
Guys and Dolls - Nicely-Nicely Johnson
A Wonderful Life - Mr. Potter
1776 - Samuel Chase
Oh, and as mentioned in the Shakespeare thread, I’m primarily a Scenic Designer
On the other hand, while I lack experience as a performer (you probably should be glad about that), my skills as treasurer (both with receipts and with pre-production fund handling) should save us from that.
Calamity Jane: Pete (a soldier—essentially a member of the chorus) - local theater last summer.
Plus, I was one of the Doper Dancers in SDMB ~ The Epic Musical Sequel 
Wicked - Elphaba (it will have to do. 'til the real thing comes along)
Penny - UrineTown
Moreen - Rent
Gonzo - The Muppey Movie
Gene Wilder - Willie Wonka and the Chocolate Factory