The 'Canary Yellow" Diamonds & Pearls Cloud Guitar as it was known then. Canary yellow was his "era/theme color" for that period, much like Purple was for 1999 through Purple Rain and Peach & Black was for the Camille/SOTT/Black Album era.
An exception to my 'Classic Prince' board - a very, very cool photo of Prince in late 1999 for the Rave The Joy Fantastic album. He just looked so amazing in this photo, should of been the album cover actually. A classic ℙℛiℕℂℰ photo and look!