The most safety way to ride in the streets is to be noticed by every vehicle.
The greatest thing you can do is to share what you have.
With this totally home made six seats tandem you could reach all theese option!
If you want to start a "think green" activity and you are looking for a new, strange and over-the-top way, what do you think about this: you can use it as sponsor but just for sports industries, or green energy companies, maybe you could be a tourist guide in your city managing a two hours ride for a family or why not, a marriage with a band riding this tandem!
Please, don't limit your creativity!
Step 1: How it's made?
The most hard part is the frame ("Oh really? You don't say?"). You have to use a professional welding machine to adapt the front and rear forks to support the weight of450-500 kg (6 people and the tandem); as you could see the rear is done welding four forks but the front has just two.
For the frame we put together a huge long empty pole at the bottom, a medium size pole in the middle and several small poles to join the big and the others two.