Converted rice is actually steamed before the husks are removed. This process causes the grains to absorb the nutrients from the husk. Converted rice is actually more nutritious than regular white rice and provides a firmer, less sticky rice when cooked. Converted rice cooks in about 20 minutes.
You can get converted (instant rice) in most any variety including white, brown and even basmati. This type of rice is used frequently in Indian cooking.
You can still buy the Uncle Ben's Converted rice in most grocery stores but if you can find an Indian market they will have many other options and very good quality too.
Instant rice is rice which has been parboiled then re-dried creating a rice product that cooks very quickly. In the U.S. the popular brand is Minute rice. Although white minute rice cooks in about 5 minutes, and the brown rice in 10 minutes you are sacrificing a nutrients and flavor.