What Is The Quickest Way To Make Some Money?

This is going to sound like a terribly obvious answer, but have you tried working?  The body can just about sustain 18 hours of work a day, so get a full time and a part-time job, nothing too physically demanding and something with half decent break periods.  Work in a call centre (sales with a bonus system) and some kind of warehouse work will keep you fit and healthy and provide a steady income.

Next suggestion, sell everything you own on Ebay and try to get the best prices for them.  Become an escort, the pay is good but it will dent your pride and your character.  

Take part in medical experiments, there's lots of companies looking for monkeys for their trials and the pay is rather good.

Failing that and I'm not suggesting these, but bank robbery and drug dealing are highly lucrative if not completely illegal and going to get you in jail for many many years.