So I will likely buy a new car late next year or early 2009.  One of my considerations is the new M3.   In the process of looking at the M3 I went to the dealer to check out the 335i sedan.  Pretty nice car.   As I researched it some more I came to the realization that the car is really cheap to modify with significant performance gains.  
Drop $1300 on an engine management device (self installed) and get 60-80HP.  NICE!  I have major mod envy. 
I realize it is so easy because of the turbo chargers but wouldn't it be nice to pay $1300 for 80HP on the Boxster  
 
 
On a side note, I have no intention to purchase a 335i, just thought it was cool that it is so easy to mod. 
Here is the site for the management device:
http://www.vishnutuning.com/bmw_335i.htm