Question

What are some ways of creating artificial gravity, other than using a centrifuge?

As you suggest, the most popular proposal for creating artificial gravity is the use of a spinning vehicle or “centrifuge.” However, we are slowing realizing that a spinning vehicle may not be the most practical solution for long-term space travel. Such vehicles would have to be built over 2.5 football fields in length to properly simulate gravity in space! One alternative idea has been the use of a “personal centrifuge” like a personal gym. An astronaut would strap himself in such a contraption for a couple hours’ spin to keep off the deleterious effects of microgravity. For more information on this research, please see http://www.space.com/businesstechnology/technology/artgravity_spindrs_001107.html Another method of creating artificial gravity (although entirely impractical) is utilizing constant acceleration. If a ship were somehow kept at a constant acceleration of 9.8 meters per second, the passengers would feel gravity the same way they do on Earth. However, the amount of fuel required for such a feat (even for a short amount of time) is entirely outside our current realm of possibilities. Other than these methods, our current ideas for creating artificial gravity remain limited due to our poor understanding of the gravitational force itself.
June 3, 2002