On Demand Open Source Software

What are some products whose demand remains unchanged regardless of their price?

In economics demand for a product is considered downward sloping. This implies that demand increases when price decreases. Is this always true? Name some products whose demand remains unchanged regardless of their price? Also mention some products whose demand increases when their prices increase?

Public Comments

1. babies will always need diapers ya have to buy them no matter what the cost
2. Funeral services.