The 1920s are definitely in at the moment, and by far the easiest way to get the look is with a cloche hat.
This flower-decoration cloche by Midnight Knitter is particularly cute, and there's a great 'making of' blog post here showing how it was done. This tutorial shows both a knitted and crocheted version and to get the effect just right, you'll need extra-chunky yarn. Instructions on how to make the flower are here.
