I was digging around on some of the performance sites for porsche such as IA, TPC, Pedros, etc. and I came across a product from IPD (Innovative Pro Design) that Sharkwerks carries for both the Box/Cay and 996/997.
http://sharkwerks.com/products.php?pid=269
http://sharkwerks.com/products.php?pid=135
A simple intake plenum.
Both applications claim between a 10-15hp gain because of the "Y" design as opposed to the "T" stock design smooths the airflow and allows more air to reach the engine.
Thoughts on this one? Part of me is skeptical and at $900+ for a cast aluminum piece....