We could write books about the magic of the Detroit square pizza. It's a wonderfully thick, crispy and cheesy treat that put the Motor City in the ranks of the best 'za in the land. But today we're paying tribute to an unsung pizza hero: the slice. When an entire square is either too much for your appetite or your pocket book, the simple slice joint will tide you over for about the same amount of change that's collecting under your car seat. Here, we've dug up 15 bargain-friendly spots that satisfy everyone from the starving student, the busy office worker, and the late night barfly .