The simplest thing you can do from old jeans, if intact upper part - it's shorts. Just cut trouser legs at the desired length and store a certain amount (to taste) longitudinal yarns to get a fringe. That's all.
Or a mini skirt. To do this, cut the trouser legs to the desired length, thrust seam running along the inner thigh, align the leg part in the new order, adjust a bit, baste and sew. The skirt is ready.
Will look nice skirt with a smell (this is mainly for jeans with a long buttoned). To lengthen a skirt, a number of buttons can be extended.
Of the remaining leg is easy enough to make cases for needles or pencils, and even a handbag for a mobile phone. In general, any suitable container size objects. You can even build a training pear stuffed trouser suitable vehicle.
Of jeans can make a great bag. Should act on the basis of which part of the survived. If you cut off the upper part of the leg at the level of education and sew it, and sew on the belt webbing to get the original bag. Useful and other remaining parts. For example, if the trousers - wide, take a section of one of them, hem, add straps - beach bag ready. Or make a new bag of scraps.
Speaking of pruning. They can be used successfully to create all things patchwork (patchwork). It covers, cushions, toys, clothing (mostly vests, jackets), as a material for applications. You can use the denim and upholstery.
If you are a handyman can try to build from jeans something like sneakers or tennis shoes.
Individual strips of jeans can be used as the original laces or as a base for weaving mats. More original use of denim to decorate picture frames, as table napkins, as the material for the manufacture of Christmas socks.
And, of course, the remains useful for denim patches on yet used denim clothing.