Here are a few of my favorites:
Implausibility of Gnus,
Dazzle of Zebras,
Scold of Jays,
Romp of Otters,
Charm of Hummingbirds,
Shiver of Sharks,
Cloud of Bats,
Pitying of Doves,
Array of Hedgehogs,
Unkindness of Ravens,
Exaltation of Skylarks,
Wake of Vultures,
Crash of Rhinos,
Parliament of Owls,
Ostentation of Peacocks,
Knot of Toads,
Flamboyance of Flamingos,
Tower of Giraffe,
Bloat of Hippopotamuses,
Prickle of Porcupines,
Gaze of Raccoons.
It would be fun to design a few collective nouns for various groups of Humans such as
a Plankwalk of Tea-Partiers,
a Spitball of Fox Newscasters,
a Brick of Black Bloc Protesters,
a Pustule of Paparazzi,
a Cocking of Gun Nuts,
a Lynch of Birthers,
a Weekend of Creationists,
an Ejaculation of Santorumites,
a Philandering of Gingrichists,
a Shifting of Obama supporters,
a Bewilderment of Ron Paulists,
a Capitulation of Romney supporters,
a Delusion of Michele Bachmannites,
an Absconding of Wall Streeters,
an Interruption of Telemarketers,
a Grandlarceny of CEOs,
a Spill of Big Oil Execs,
a Ransom of Lobbyists,
a Gist of Reporters,
You get the idea. Do you have some ideas or suggestions to add to the list?