Knowledge Base content for customizations building

I would love to see some portal customization techniques. As well as first steps in customizing an existing page in lieu of creating one from scratch.
The stuff mark touched on in the webinar was fascinating but did not touch on that side of things. It may seem basic but, if you don't know basic, it is hard to learn advanced. ô¿~

Could you revisit PXFormula?  I feel like it is a good stepping stone into getting some more complex business logic through straightforward attribute customizations, but the more interesting uses are only scattered around in blogs and stack overflow posts, missing from the PXFormula KB article.  Getting some range of simple to detailed examples of PXFormula(typeof(Selector<>) and PXFormula(typeof(Default<>) would be a great way to demo getting strong business logic at an intermediate skill level.  Especially getting these to work with your own DACs and DAC extensions.  Also, are there more of these hidden away?  Would be nice to know!