Marek, here are some highlights:
The coast road Andratx - Banyalbufar - Deja - Soller. Either the whole thing or turning off at Valldemosa. Brilliant in either direction, but slightly scarier doing it southbound as the huge drop to the sea is closer.
Puig Major (Soller to Lluc or vice versa), taking in Sa Callobra (time and climbing-legs permiting).
But my personal favorite is the Bunyola - Orient - Alaro road which goes through a beautiful hidden valley high in the mountains.