The Longines Symphonette's Complete Treasury of Nostalgic Holiday Music - Christmas at the Fireside
Aside from the twenty I found in a mud puddle outside the barber shop when I was ten, or the hundred dollars I found in Vancouver B.C. when I was completely broke on vacation as a teen, this may be the greatest ground score I have ever come across.
Walking home from the bar one hot summer evening, I picked it up from a free pile in front of Clinton Street Records, knowing it would provide much needed Christmas cheer later on down the road. And it surely has. The four record set has been a holiday favorite at our apartment for the better part of a decade now.