Alter value of field before loading I'm just wondering if its possible to alter a field before loading.

Here is the situation. 

Im using commerce kickstart.

When I'm in a product page(inner page or product details page), I want to change the value of field_my_field before it load up to the page. 

In pseudocode:
If field_my_field == "something" change field_my_field to "my custom value"
It is very easy! where do you want to display the field?

If it is a view, then you can use template_preprocess_views_view if it is a node, you can use hook_preprocess_node function to alter the values. where your content is going to be displayed?