James Lipton -- "Marvelous!"

I mostly know James Lipton from those Geico commercials and Will Ferrell making fun of his "Inside the Actor's Studio" on "Saturday Night Live," but I recently found out that he has some other claims to fame.

Such as, he's married to the woman who was the original "Miss Scarlet" in the game of "Clue."
Also, I just discovered that he's written a book on collective nouns called "An Exaltation of Larks." If you're grammar-challenged like I am, a collective noun is what you call a group of things. Some of the most common ones are...

...a school of fish...

...a gaggle of geese...

...and a murder of crows (one of my favorites).

The first part of the book is what you would expect -- a boring treatise on the origins of collective nouns. But then it gets fun. It turns out that a lot of these terms came about through a game played by 15th century well-to-dos (with obviously a lot of time on their hands) who just sat around and came up with these sayings.

In that spirit, James Lipton fills up the remainder of the book with such delightful phrases as:

A pound of Englishmen, a pint of Irishmen, a fifth of Scots, a smorgasbord of Swedes.

A wave of Hawaiians, a mass of Bostonians, a spread of Texans, and a mush of Alaskans.

An unemployment of graduates, a charge of shoppers, and a flush of plumbers.

An ingratitude of children, a consternation of mothers, and a distraction of fathers.

A rash of dermatologists, a void of urologists, and a plague of epidemiologists.

An immersion of Baptists, a visit of Jehovah's Witnesses, and a book of Mormons.

Now it's your turn. What would you call a group of:

Firefighters? Hummingbirds? Unicorns? Shopping carts? Clowns?