Yes. Surgical removal to use of certain lasers and radiofrequency devices will provide a tightening effect. Lesser effects come from muscle building to increase mass, creams, injections (fillers and fat grafting), etc. Do offer some filling options to improve the appearance of loose skin.
Nip & Tuck it. While advertisments offer the promise of skin tightening machines, lasers, lotions, potions and peels, most of these technologies are only capable of delivering skin tightening (on a scale of 1 to 10) at a maximum level of 3. If that is all you need these devices may work for you. If, however, you need a level of 7 to 10 skin tightening, skin removal is essentially the most reliable method.
Excised or cut. Depending on the location and amount, skin can be excised or cut, leaving a scar. There are some machines that use ultrasound or radiofrequency waves to heat up deep tissues which can pull on the skin. These machines have variable success.
Yes and no. There are no exercises that will tighten skin. This will only build up underlying muscle that may help with minimally loose skin. Some types of laser and thermage can help to tighten minimally loose skin. Surgical removal is the only way to "tighten" very loose skin. You will trade loose skin for a scar placed in the least conspicuous place possible.