Surely its:
An sue of penises
A listing of programmers.
A puzzle of analysts.
A muddle of managers.
A pounding of data entry clerks.
An exasperation of users.
I’m blanking on this one. A smooch of herpes?
I am thinking very little of it as I post.
My grammar pals came up with “an agreement of grammarians.”
HA! I read this the “right” way first and was confused by being told to think about it, then I caught it out of the corner of my eye and realized how it should read. 
Interesting! Thanks, everybody. How about:
A disputation of Dopers.
A cecil of Dopers.
A draggle of Dopers.
A hi-opal of Dopers.
An airplane-on-a-treadmill of Dopers.
A doration of Dopers (think about it!)
I like to refer to groups of snowboarders plunked down on their butts fastening their bindings as a ‘pod’ or a ‘raft’.
I’d always described them as “a collection of pros.”
From this thread – http://boards.straightdope.com/sdmb/showthread.php?p=5845626:
an abomination of demons
an unobtanium of unicorns
a nubility of nymphs
an orgy of satyrs
a shitstorm of pegasi
I prefer a “flourish of strumpets” myself…
A haggle of shopkeepers.
A jackpot of gamblers.
For the record, one more variation (don’t remember where I saw it):
An anthology of pros.