I I was experimenting lately with page items and how to setup APEX page (preprocessing section) in more cleaner, reusable and generic way. I also wanted to move the logic from APEX to PL/SQL packages to fulfil my MVC vision (to keep as much as possible code in PL/SQL, not in APEX). So I made this up. For every page in application I have created a package, "P0" for page zero, "P100" for page 100... For 100 pages I would create 100 packages, but that is still better then have the logic scattered on individual pages. And most of the times I have to create packages anyway because I need a place where to store form/grid handlers and page related logic. Then I have created INIT_DEFAULTS procedures in each of these packages. And in this procedure I setup page items and run the pre-rendering processes. Since we are talking about packages, I can reuse other procedures and function and limit the amount of copy pasted code. I use my wrapper around these session state call...
Mainly APEX, sometimes SQL, PL/SQL, clean code and certifications