"Good King Wenceslas" is a very popular carol that is usually performed jauntily in 4/4 time by choirs and soloists alike. Glenn Jarrett's novel variation for guitar on "Good King Wenceslas", in 3/4 time, has a jazzy feel about it but the original melody is still recognisable. A short introduction using chords of the harmonised D major scale leads into the verse. Glenn suggests that this introduction might be useful for guitarists wishing to add his variation as a second verse to a more orthodox arrangement of the tune in 4/4 time - not necessarily in the key of D major.
On mfiles we also have "Good King Wenceslas" in a more traditional arrangement for piano with options for other instruments.