In the interest of maintaining a comprehensive list there are **four** primary ways of moving minecarts:

 1. Physically pushing – it's slow, and boring, but it's one way of transporting lots of goods a great distance.
 2. Gravity – It's a one-way method of transportation, but you can gain quite a lot of distance from a minecart track that's sloped correctly.
 3. Furnace-carts – Furnace carts are wonderful for traversing flat terrain with minimal track-usage. Coal/Charcoal is quite common, and makes a furnace-cart a good way to transport goods remotely without using quite as much iron ore.
 4. Boosters – The fastest way to travel, boosters are great for traveling really far, really fast. They do have some issues, however:
    * Boosters consume a lot of iron ore to create the carts/track that sit idle the majority of the time
    * Boosters may be removed ("fixed") in a future update, as they were an unexpected "feature".

One method of "fast" travel involves hopping in and out of a minecart while moving to use the pushing effect to move at a reasonable speed.