By pure coincidence, while I was reading this thread, I was listening to Bing's Collectables compilation In Hollywood Volume Two, and Bing was doing some fine whistling on "Just an Echo in the Valley," from the 1933 movie Going Hollywood. So that is my first nomination! By the way, I had almost forgotten what a great soundtrack Freed and Brown wrote for Going Hollywood...

I seem to remember that on Bing's Musical Autobiography set, he prefaces "Just an Echo in the Valley" by mentioning that it was one of his theme songs. I was under the impression that Bing's only theme song was "Where the Blue of the Night &c." Any thoughts on this?

Steve Fay wrote:

Fellow Crosby fans -- recalling all of Bing's songs that stick in your memory partly because of Bing's very above average whistling included in some passage, which of those songs do you think represent his best whistling and that are also great songs in total?  Would there be enough of these to make a compilation CD?  Please post your nominations, whether naming single songs or the list of your Bing-the-whistler favorites.

Let me start out by volunteering one I consider essential, an example of vituoso whistling, "Honeysuckle Rose," in which Bing not only whistles very jazzily and amazingly, he also actually seems in places to be whistling more than one note at a time IN HARMONY!

I eagerly await others' nominations.

Steve, someone produced a list of all the songs where Bing can be heard whistling - I know I have it but I can't remember where it appeared! I think I'd need it as a prmpt before puzzling out what I might prefer! 
 

Thank you for the reminder, Malcolm
The list according to Fred Reynolds, in chronological order, is -

First Era – 1926 – 1934
From Monday on
It was The dawn of Love
I kiss your hand, madame
Gay love
It must be true
Wrap your troubles in dreams
Just one more chance
Many happy returns of the day
Star dust
A faded summer love
Goodnight sweetheart
Where the blue of the night meets the gold of the day
Can't we talk it over?
Starlight
Shadows on the window
Paradise
Waltzing in a dream
Lazy day
Please
Linger a little longer in the twilight
Let's put out the lights
Just an echo in the valley
Young and healthy
Shadow waltz
The day you came along
The last round-up
I'm hummin', I'm whistlin”, I'm singin'
Let me call you sweetheart
Love is just around the corner

Second era 1935- 1941
I wish I were Aladdin
Take me back to my boots and saddle
Moonburn
We'll rest at the end of the trail
Robins and roses
Me and the moon
In a little hula heaven
My little buckaroo
Dancing under the stars
Sail along, silv'ry moon
Bob White
Silver on the sage
It must be true
Whistling in the wildwood
Wrap your troubles in dreams
Girl of my dreams
Start the day right
The girl with the pigtails in her hair
I haven't time to be a millionaire
Mister Meadowlark
A song of old Hawaii
I found a million dollar baby
Where the blue of the night meets the gold of the day
Mary's a grand old name
The whistler's mother-in-law
Shepherd serenade

Third era 1942-1950
Lily of Laguna
Wait till the sun shines, Nellie
White Christmas
Along the Navajo trail
Where the blue of the night meets the gold of the day
Friendly mountains
White Christmas
The Christmas song
Alexander's ragtime band
Memories
Blue shadows on the trail
Weddin' day
Sunshine cake
The last mile home
Top o' the morning
I didn't slip, I wasn't pushed, I fell
Accidents will happen

Fourth era 1951-1960
I whistle a happy tune
A weaver of dreams
Rosaleen
Just a little lovin'
Tenderfoot
Wrap your troubles in dreams
Paradise
Little one
Blues in the night
Honeysuckle rose
Georgia on my mind
I'm confessin'
Git along little dogies
You were meant for me
Linger awhile
I was seeing Nellie home
Oh, them golden slippers
Toot, toot, tootsie
It's a good day
Shine on harvest moon
Listen to the mocking bird
While strolling through the park
Won't you come home, Bill Bailey?
Tramp, tramp, tramp

Fifth era 1961- 1977
Singin' in the rain
Five foot two, eyes of blue
Cecila
Oh, lonesome me
The poor people of Paris
Where The Rainbow ends
La Borrachita
The only way to go
Beautiful memories
April showers
The only way to go

The spanner in the works is that there are of course other examples, drawn from radio and "recorded for radio" material.
Some titles crop up several times.
Far more than I had expected and I still don't know which I prefer.
Any other responses to Steve's challenge?
 

In the film Pennies From Heaven, I love when Bing whistles at the end of the title song while lighting a pipe and smoking it. Classic Bing!

In connection to recent news that BCE will be releasing new CDs and DVDs on a regular basis again, I wonder what number and variety examples of Bing's whistling they might have in the massive Crosby media vault?  If they are taking suggestions for future releases, I (and perhaps some of you would join me) would love to see/hear a CD or CD set that displayed Bing's stature and range as one of the best whistling singers in recording history.  I don't think his accomplishments in that realm are likely to be equalled in a very long time, if ever.  Perhaps the world would benefit from being reminded of that.