How does Piracy work?
The correct response as an opponent is to tap all lands they control.

No, fizzle means to counter a spell on resolution. This is the result of a spell having zero legal targets. This spell isn't targeted, so it cannot fizzle. Since the Magic 2010 rules changes, mana burn no longer exists, so your opponents can just tap all their lands for mana to prevent someone else using the mana to cast their own spells.

If your opponents allow the spell to resolve and take no actions, the player that cast Piracy is likely the active player, which means that they would receive priority to cast spells. This would allow them to use any opponent's land to pay for casting their own spells.

No, there isn't anything interesting you can do with this spell now, it is a {U}{U} spell that taps your opponents out.