Leather
Pros: Fairly common in regular clothing stores (unlike latex and the like), warm in winter, long-lasting
Cons: Expensive, hot in summer, not animal-friendly, difficult to clean, must avoid fluids

Impact play
Pros: Can use a variety of implements or just hands, can be soft or hand, can be performed on a variety of body parts
Cons: Can be dangerous, top may become fatigued

Bondage
Pros: Rope is easily found, can be bound in a number of different ways
Cons: Possibility of nerve damage, cannot stay in the same position for too long, difficult/dangerous to perform alone, requires knowledge of knots etc.

Sensation play
Pros: Many household items can be used, cheap
Cons: Doesn't have much effect when performed on self

Consensual non-consent
Pros: Versatile in terms of role/situations
Cons: Requires careful negotiation, difficult to act like you don't want it (at least for me!)