What a great topic! I love orange and purple plant combos:
Lion's tail or any of the sunset-colored flax with a catmint "petticoat".
Fine-textured perple Verbenas with the bronze-leaf and butterscotch-flowered Cannas.
Russian Sage and orange Sunrose.
Purple agastache and Carex buchannonii
Califonia Poppy surrounding Lavender 'Grosso'. I use a sprinkling of the coastal form of Ca Poppy mixed in with the huge orange ones. Tones them down a bit.
I think the softer lavender of catmint pairs beautifully with the trendy reds and corals available now in the newer phormiums and coprosmas. I'm very smitten with those warm colors.