Right now there is a surge in the curiosity amateur scientists in backyards and garages across the country and the world. People are realizing the power, versatility, and interesting properties that hydrogen has to offer. Now to be clear, what I am referring to when I say hydrogen is actually something called HHO or Brown's gas, which obviously contains an oxygen atom as well. Brown's gas is extremely combustible, and its exhaust is only water vapor, making it 100% clean.
You may have never heard of this gas or what it can do, but it has come to be used in some interesting places.
Many people have had quite a bit of success adding a generator to their vehicle and wiring it into their battery with the aim of increasing gas mileage. Others have found that HHO makes for an exceptional torch for certain uses, such as glassmaking. The flame is unusually cool when in contact only with air, but when applied to the surface of different metals heats up to incredible temperatures. Relative to other electronic welders, hydrogen fuel generators fitted with torch tips use very little electricity. Another advantage is the stability of the fuel, distilled water, which is completely stable. Since the gas is produced on-demand there is never a huge tank of combustible or toxic fuel nearby, which is a huge safety benefit.
The average person in their home is able to generate hydrogen using the process of electrolysis. A cathode and anode are placed very close to each other, and a current is applied. The water that conducts the electricity between the positive and negative points fizzes with HHO. An electrolyte such as baking soda can be added to increase conductivity, which in turn increases amperage and consequently gas production.
Since you are trying to "electrify" as much water as possible simultaneously, you want to trap as large a surface area of water as you can between the cathode and the anode. Metal plates are used for this purpose, and stainless steel is the only acceptable material as all others corrode extremely quickly, filling your system with gunk. Electricity can be supplied by a modified ATX computer power supply, a car battery, or something similar for testing. If you want to prove the concept in an incredibly simple way, just drop a nine volt battery into a glass of water, and you'll see tiny bubbles begin to rise from between the terminals at the top of the battery.
So now that you have a hydrogen fuel generator in your own home, what are you going to do with it? Well, the community of experimenters is still budding, so there are undoubtedly undiscovered uses for this incredible substance. The best way to contribute to the community and help make new advances is to safely experiment for yourself! Since the investment cost is relatively low, it doesn't take much commitment to get started. Look at other individuals' designs and prototypes, decide what approach looks most appealing to you, and get started. Once you have a basic prototype functioning, try different methods of increasing your efficiency, and share your results with others interested in the subject as well.