Evelyn Series' of Interlocking and Mosaic Crochet Patterns - Ashlee Brotzell Designs
22 Free Crochet Patterns for Every Skill Level
Interlocking Crochet Patterns - Kathryn Clark Crochet
Samples. Trying out Martin up North's Connected cushion design in interlocking crochet. Also playing with reversing the contrast. Free pattern on his blog written for mosaic crochet, link in the comments. :
Interlocking Crochet Patterns - Kathryn Clark Crochet