Russian Join - No more weaving in ends! Hate weaving in ends? The Russian join is an excellent technique for attaching a new skein of yarn or for changing colors. Best of all, it creates a secure join, so you can keep crocheting or knitt.
This pattern is for knit slippers, but I can totally see using a wool sweater and cutting and serging slippers from it! Home Slippers - DIY. this is knitting, but I bet I could use this to crochet some
Interesting set-up for socks. You do the top of the foot first, then a short row toe, and finally you work the bottom of the sock in stockinette picking up stitches along the edges. Free pattern on ravelry
This decoration for knitted projects looks like Latvian Knitting, but is really just crocheted slip stitches made into a knitted foundation. It's really easy to do and is a very effective way to add design interest to your knitting.