Practical Crocheter and I have collaborated to put together a pattern booklet with five different slipper patterns. The first pattern is the classic pixie/slam dunk slipper pattern, with advice on making that design more practical and a chart to help you make it in any gauge or size. The four patterns that follow that one are progressively more involved variations on that basic design. All of them can be made in any size and any gauge, and they all include a description of our design processes in order to encourage you to try your hand at doing your own design work.
Pixie Slipper Pattern Booklet