Oh, sure -- you've got at least 893.1 options (at last count, anyway) when it comes to noise cancelling headphones for your iDevice, but do any of those plug directly into the dock connector instead of requiring a separate battery? Exactly. That's the claim to fame for Blackbox's i10, a new set of earbuds that rely on power from your iPod or iPhone in order to achieve that active...
If the Playaz N1 were designed with reasonable amount of bass and they could be the steal of the century. In reality I can recommend them for EQ-friendly folks only - stay away if your source does not have a good, user customizable EQ.