Companies of Intrest

SpaceX

Known for making vertical launch systems reusable and far cheaper than the competition by using retrorockets for landing the boosters, and catching the aerodynamic fearings in large nets
Their Website

A hobbyiest group attempting human spaceflight
User:Eric speaking here, on my personal, non business youtube account (i think, i'll double check just in case) i asked and they said they wanted to be open source, but had to not be due to the risk of missile development by nefarious groups
Their Website

A company who makes the Electron Launch Vehicle, which is one of, if not the, smallest orbital launch platforms
This is useful, as many payloads, such as Cubesats need to get to orbit, but do not need a large launch payload overall
Thus the Electron Launch Vehicle saves money for groups looking to launch small payloadss, and lowers the barriers to entry into the feild
Their Website

A group specializing in Inflatable Space Habitats, which allow for large space habitats with relitively small launch volumes
Their Website

A group specializing in combined cycle, precooled hypersonic engines
Their main development is Skylon, a SSTO HTOL Spaceplane
Skylon is an ofshoot of the British Aerospace HOTOL Program
If successful, this will allow for heavily reusable, and safe delivery of cargo, and human payloads to orbit, on a reliable basis
Also the horizontal takeoff and landing is more familiar to the average person, and thus may be more approachable to the average person than vertical launch solutions

This company has been put on hold, mostly due to spaceX reducing its place in the market, but it still may have a place
This is a company that proposed a SpaceGun utilising a Light Gas Gun based of hydrogen as the light gas being pushed, and natural gas for the explosive push
it would consist of a 1.1 km long pipe submerged in a body of water at an angle. It would accelerate payloads to around 6km/s. A small booster would be used for circularizing the orbit, but price would be dramatically reduced
This would not be human rated, but it could be very beneficial for resupply and/or fuel depot refueling
This would also have a rather fast relaunch time as all that is needed is the insertion of a new payload, and gas repressurization
Barrel wear is one concern
Some groups propose the use of a coilgun or railgun for a similar but electric approach, which especially makes sense in enviroments with lots of sunlight (for electricity generation), and low temperature + air pressure. Earth's moon is one such place
The Wikipedia Page on Quicklaunch