From beginner to expert, Crochet Compendium: The Ultimate Collection of Crochet Techniques by Connie Ellison will point you to something new and different from your usual project.
You'll find pages and patterns for such techniques as mosaic crochet, slip-stitch crochet, wiggly, waffle-weave, tunisian or double-ended crochet, hairpin lace, broomstick lace, felting, and filet crochet. That isn't the complete list.
There are full-color photos to help you understand what to do. There is also a chart to help you understand crochet symbols. If you can't figure out the written pattern, it sometimes helps to see the symbols forming the design.