Here are some pictures of purple foods. The Boy and I loved the cauliflower, the potatoes weren't as big a hit. They had an oddly sweet taste when mashed.
When made into mashed potatoes the purple potatoes turned more blue than purple.
The color in the raw potatoes was so much nicer than the end color. No one liked them all that much, I had thought I'd make them baked next time, but they aren't worth the extra money. I wonder why they are purple and if they have different nutritional value than russets. Hmmm I guess I'll have to look them up.