Soft Bodies
Another way to go is with a soft body dynamics system. For those with Maya or 3D Studio Max, a soft-body dynamics system provides one option for cloth. Soft-body dynamics treats each vertex in your mesh as a particle, which allows for real-world simulations. Many systems can also employ a simple mass spring mechanism, which is the underlying process for most commercial cloth plug-ins (although not as finely tuned). For Max users, flex is one option, and soft-body dynamics are another for those using Maya.
Using a soft-body system can be a mixed bag. Because most soft-body systems cost as much as a cloth plug-in itself, it may behoove the animator to use a cloth simulator because most soft-body systems fall a bit short when it comes to the tough real-world simulations that cloth requires. On the other hand, although soft-body systems are not as finely tuned to the demands of cloth, they are more generic and versatile for many other types of effects.