Granny squares are charming in an old-fashioned way. They make for cute blankets and pillows, and I've seen crochet books with clothing entirely made of granny squares. They are cute little projects you can put in your purse and crochet on the bus, for example. Or you can make them with scraps of yarn. Yes, but there's always the downside: there are so many threads to weave in! And you have to stitch them together. I'm not a huge fan of weaving in or sewing/crochetin things together. I bought a book called "Seamless crochet" which deals with that issue and teaches you how to crochet motifs together while working them. Haven't mastered that one yet, there's a pattern that looks like I could build a time machine with it ;-)
A couple of months ago I made two granny square baby blankets. I like how both of them turned out, but the one with the multicolored squares was a bitch to finish ;-)
This one was made with two threads Drops Alpaca in four different colours.
Here is the pattern This is my favorite. It's made with Drops Nepal, a great bulky yarn. I love the colours, especially the gray/purple and the gray/green.
Here's the pattern To be honest, one of my ufo's (unfinished objects) is this blankie in different colours. I finished the squares, but I'm not in the mood to assemble them..... urgh.