Competition can be a powerful incentive for creativity, leading some engineers, scientists and do-it-yourselfers to achieve breakthroughs in their fields. Aside from the prestige of winning a contest against one's peers, cash prizes offer an additional benefit for the inventive contestant. Here are some unique and fascinating prize contests that can be challenging and (hopefully) rewarding for the would-be competitor.

The N-Prize
If you've ever wondered what it takes to be a do-it-yourself rocket scientist, the N-Prize challenge might be for you. The contest asks an individual or team to build and launch a satellite into Earth's orbit on a budget of £999.99, or about $1,661.

Contestants that launch a reusable vehicle are allowed to exceed the budget, as long as the recovered hardware brings the per-launch cost down to the price cap. According to the contest rules, "the N-Prize Challenge is intended to encourage creativity, originality and inventiveness in the face of severe odds and impossible financial restrictions."

Winners receive prizes of £9,999.99 for both reusable and non-reusable launches.

The Regolith Excavation Challenge
In the field of space exploration, the moon still has a great deal of valuable knowledge to offer. The Regolith Excavation Challenge, sponsored by NASA and the California Space Education and Workforce Institute, tasks teams with building robotic systems to dig through simulated lunar soil (regolith) in order to develop lighter-weight and lower power-consumption excavation tools.

The teams that construct robots capable of moving the largest quantity of regolith in a given time can win a first prize of $500,000, a second prize of $150,000 or a third prize of $100,000.

According to the competition rules, "advances in lunar regolith extraction have the potential to significantly contribute to the Nation's Space Vision and space exploration operations."

The Green Flight Challenge
For the goal of building a more efficient type of aircraft, NASA and the Comparative Aircraft Flight Efficiency Foundation (CAFE) have organized the Green Flight Challenge, a contest to develop a plane that can average at least 100 mph on a 200-mile flight while maintaining fuel-efficiency above 200 passenger miles per gallon.

"To win," according to the sponsors, "teams must use cutting-edge technologies in mechanical and electrical engineering, structures, aerodynamics and thermodynamics," which "will support advances in aviation and may have broader applications in transportation and energy storage."

The top award is $1.5 million, while the entire prize purse is worth $1.65 million. The complete contest rules can be found HERE.

Automotive X Prize
Much like the Green Flight Challenge, the Progressive Insurance Automotive X Prize is a competition intended to spur the development of high-efficiency, low-emission automobiles that can appeal to both automakers and consumers.

The contest is essentially a race in which vehicles must meet a 100 miles-per-gallon equivalent standard, using either gasoline, electricity, bio-diesel, fuel ethanol, compressed natural gas or any other power source that can realistically be on the marketplace by 2014. In addition, the cars must pass safety and production capability criteria in order to be as close to market-ready as possible.

According to the competition guidelines, the emphasis is on "production-capable new vehicles and existing-vehicle modifications, not concept cars." Winning teams will split a $10 million prize purse.

The Tether Challenge
Advancing the progress of construction in space will likely require new materials to meet the difficult conditions presented by a low-gravity vacuum environment. To that end, NASA and the Spaceward Foundation have established the Tether Challenge, in which teams must construct a tether that exceeds the maximum strength of the best available commercial tether by at least 50 percent. The catch is that it must be stronger without adding any additional mass.

According to NASA, there is potential for "wireless power transmission and high-strength tethers being combined to realize the space elevator, a concept that would bring about a revolution in space activity."

Each tether must undergo a pull test, and the winning entry receives a $2 million prize.

The Saltire Prize
Harnessing the energy from a powerful and ubiquitous source of motion is a major goal for both private enterprise and governments. For that reason, the Scottish government founded the Saltire Prize in 2008 to encourage research on channeling the power of the ocean.

This contest awards £10 million, or $16.58 million, to a team that develops a commercially viable wave or tidal energy technology capable of producing at least 100 gigawatt hours (GWh) continuously for two years.

The system must rely solely on sea power and has to be demonstrated in Scottish waters. The competition guidelines are available HERE.

The Astronaut Glove Competition
Gloves are some of the most challenging design features of an astronaut's suit. Because they are pressurized, the gloves resist bending, forcing their wearers to strain and sometimes injure themselves, while the joints are prone to wear that can cause pressure leaks.

The Astronaut Glove Competition, sponsored by NASA and Volanz Aerospace Inc., is intended to address these problems. Competitors are tasked with improving the durability of the glove, and must demonstrate their design in a series of specified tasks.

According to the competition rules, in addition to dexterity and flexibility evaluations, the gloves must also undergo a "burst pressure" test to determine their strength capabilities. The 2009 purse prize is $400,000.

Earlier

Sweepstakes Science: Prizes for Breakthroughs

Lunar Challenge Underway

Start Your Engines In the Race for Green

Design a Tech Lab, Win $250K

Homer's Glove

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NASA Joins New Competition, Calls to Private Industry: $2.5 million Prize

Why Take a Rocket Ship?

Resources

The N-Prize

Regolith Excavation Challenge
California Space Education and Workforce Institute, July 12, 2009

NASA and CAFE Announce Green Aircraft Challenge
NASA, July 31, 2009

Competition Guidelines
Progressive Insurance Automotive X Prize, Jan. 13, 2009

Tether Competition
NASA, Sept. 1, 2009

Saltire Prize Draft Guidelines
The Scottish Government, Jan. 2009

Astronaut Glove Competition
NASA, Aug. 25, 2009

2009 Astronaut Glove Challenge Rules
Volanz Aerospace Inc., Aug. 1, 2009