Useful software for < $50 on the App store? Buy.
Useful iPhone app for < $10? buy
Useful software I use rarely for $800 (Adobe CS5.5)? Pirate
Drm free music album for $10? buy
Movie rental I can't find on iTunes for < $5? Pirate
TV Show season on-demand without commercials? Netflix, or Pirate
Any time it's easier and relatively inexpensive to buy, I'll do that. Any time it's a pain to buy, obscenely expensive or a worse experience, I'll pirate.I don't justify that behavior, but I've noticed I buy when it's easier, and I pirate when it's easier.