Comedic (Most commonly used)

Uses:
The Check's In the Mail
Another One Rides the Bus
Eat It
Midnight Star
I Lost On Jeopardy
King Of Suede
That Boy Could Dance
Theme From Rocky XIII
Nature Trail to Hell
Yoda
Slime Creatures from Outer Space
This Is the Life
Cable TV
Living With A Hernia
Addicted To Spuds
One Of Those Days
Here's Johnny
Don't Wear Those Shoes
Toothless People
Christmas At Ground Zero
Fat
Stuck in a Closet with Vanna White
(This Song's Just) Six Words Long
You Make Me
Lasagna
Melanie
Velvet Elvis
Twister
Generic Blues
Spam
The Biggest Ball of Twine in Minnesota
Smell Like Nirvana
Trigger Happy
I Can't Watch This
I Was Only Kidding
The White Stuff
When I Was Your Age
The Plumbing Song
Jurassic Park
Bedrock Anthem
Traffic Jam
Talk Soup
Livin' in the Fridge
UHF (single version)
Amish Paradise
Gump
The Saga Begins
Pretty Fly For A Rabbi
Grape Fruit Diet
Alberquerque

Abuses:

Buckingham Blues
Happy Birthday
My Bologna
The Brady Bunch
Mr. Popeil
Girls Just Want To Have Lunch
Here's Johnny
Alimony
Airline Amy
Young, Dumb & Ugly
She Never Told Me She Was a Mime
I'm So Sick Of You
Syndicated Inc.
*Spy Hard

Borderline:

Gotta Boogie
I Love Rocky Road
Such A Groovy Guy
I Want a New Duck
I Think I'm a Clone Now
Attack of the Radioactive Hamsters from a Planet Near Mars
Waffle King
Everything You Know Is Wrong
Cavity Search
Callin' In Sick
I Remember Larry
Phony Calls
The Night Santa Went Crazy
My Baby's In Love With Eddie Vedder
The Weird Al Show Theme

Half Comedy, Half True Tenor:

Stop Draggin' My Car Around
I'll Be Mellow When I'm Dead
Mr. Frump in the Iron Lung
Dare To Be Stupid
One More Minute
George of the Jungle
Dog Eat Dog
Good Enough For Now
Good Old Days
Money for Nothing/Beverly Hillbillies
Isle Thing
UHF
Let Me Be Your Hog
You Don't Love Me Anymore
Frank's 2000" TV
Achy Breaky Song
Harvey the Wonder Hamster
My Bologna (Capitol Records)
Happy Birthday (Placebo E.P.)
Since You've Been Gone
Jerry Springer
Germs
Your Horoscope For Today
It's All About The Pentiums
Truck Drivin' Song

Falsetto (2nd Soprano)

Mr. Frump in the Iron Lung (at the end)
Polkas On 45
King Of Suede
Like a Surgeon
Hooked On Polkas
Polka Party!
The Hot Rocks Polka
Let Me Be Your Hog (at the end)
She Drives Like Crazy
Polka Your Eyes Out
The Plumbing Song
Jurassic Park
Bohemian Polka
The Alternative Polka
Since You've Been Gone
I Remember Larry (at the end)
*Spy Hard(the ending)
Polka Power!

Falsetto (Baritone)

Gotta Boogie
The Brady Bunch
Nature Trail to Hell
One More Minute
George of the Jungle
Dog Eat Dog
Toothless People
Good Enough For Now (a little)
Money for Nothing/Beverly Hillbillies (towards the end)
Isle Thing
Let Me Be Your Hog
I Can't Watch This
The White Stuff (a little)
Taco Grande (a little)
The Plumbing Song
Harvey the Wonder Hamster
Headline News
Since You've Been Gone
Pretty Fly For A Rabbi
The Weird Al Show Theme
Jerry Springer
Germs
It's All About The Pentiums
Truck Drivin' Song

Impersonations

Ricky
Like a Surgeon
One More Minute
Girls Just Want To Have Lunch
Living With A Hernia
She Drives Like Crazy
Headline News

Real Accents

Al's Characters