This won't be a formal tutorial since these are just follow-the-pattern creations (modified Butterick 5498 and Butterick B5284) but I wanted to show you all what I worked on this weekend :)
This draped / gathered cardi used a lightweight knit and was created by widening the front flaps by 4" (left flap that's swept over) and 2" (right flap). Then I just manipulated the left flap a little bit for frayed edges and scrunched it for some pleating. The buttons are decorative rather than functional and the closure is a simple hook and eye. Total project cost: $6.
Here's another picture to show the shoulder detail:
The second project was inspired by all the J. Crew and LOFT ruffled button downs that I've seen all over the place lately. This is a shirting fabric from Joann's. Total project cost = $9.