easy crown molding using "cheater pieces" at the corners. No mitering required. http://thriftydecorchick.blogspot.com/2013/05/cheater-crown-molding.html
Dress up your windows with crown molding. | 40 Easy DIYs That Will Significantly Upgrade Your Home home improvement hacks
How to Create Faux Crown Molding (also an idea for the imperfect ceiling entryway)
Cheap and easy way to do crown moulding
Great craftsman-like "crown" using pieces of wood. Not even set at an angle. EASY AND LOVE!! From Tidbits from the Tremaynes
A blogger in Arizona made this chic valance using MDF wood and crown molding left over from a kitchen renovation.
Use 1″ x 4″ MDF boards and some 3/4″ round wood molding instead of traditional crown molding ... much, much cheaper!
DIY door casing because we'll need to replace the ones in the dining room if we ever move
Peel and Stick Crown Molding
Great tip! A really easy way to figure out tricky angles when you're installing moldings, trim, and baseboards.