Set the shipping of a quote to amount X globally?

Question

Is there a way to say that if a certain criteria is met, set X EUR shipping for a current quote from the cart globally? Like this:

 if(someCriteriaIsMet) {
     //set the shipping to 5 EUR so that the cart, the OPC review and so on show that amount    $amount = 5;
 }

The question is, is that possible at all and if yes, where would I put that code?

Thanks!

Answer 1

Short chat with @thebod and searching in the code shows:

No, not so easy. There is no event you can hook into, so what you can do is implement your own shipping extension, add whatever check you want and then return the amount you want.

A start how to do is, might be at smashing magazine