You could always look into being a rep for a utility company. Hard work building a customer base mind but can there is money to be had whilst giving your customers a saving. It's worth a thought, don't expect to retire anytime soon though and try not to listen to all the bull they feed you.
I joined one about 10 years back, got about 6 customers and gave up trying. It's VERY frustrating work, mainly convincing people that you can save them money.
I can only comment on one company utility warehouse, they have a large array of loss leading services that are designed to hook the customer in. I can honestly say that it's not a rip off in any way, im still a customer myself after 10 years.
The fact is this, the company and you as a rep, only really earn money from the customers gas and electric usage. All the other things the customer uses like phone, mobile, internet, loyalty card etc earn you bugger all

But they do save the customer lots of money, which in tern keeps them happy and makes them stay with you. You earn a percentage of their gas and electric usage as long as they stay a customer.
They operate the business with a "tiered marketing strategy" and if you have any brains you'll think Pyramid scheme. Most people do, but there's a fundamental difference between the two. A pyramid scheme has no product and thus is a con that will eventually crash leaving many people skint and a few very rich and on the run

I still have my site but can't be arsed recruting customers or reps these days as I got very fed up trying

But I can tell you that it works for some people, just don't expect to get rich quickly or at all.
The fact that you have a captive audience "your customers" is a very good start. That's half the problem solved, the other is getting their business

Once you've got them it's very unlikely you'll lose them trust me.
It cost me money to become a rep, about £250 I think, but I'm fairly sure it's no longer that much, in fact there are ways to become a rep for nothing I think. As a customer you can refer others and make money from it, but I don't think you're allowed to recruit other reps.
Have a read
www.energywise.co.uk and see what you think, I'll honestly answer any questions you might have. They key to success is basically to get about 20 customers, then 5 reps and get them to find 20 each and so on blah blah, once you've set them off hopfully they will continue to replicate and your half way to global domination

Good luck