A liquid asset is one that is easy to cash in. What is the most liquid asset?
Which is more liquid, a savings account or a loan to a business?

it's actually a very difficult task, due to not many people can make 2 million dollars in 2 years. besides that, to the not-so-realistic ideas, you can create a business. it could be practically anything, but make it into a business that isn't that known yet, you get me? also, lets not forget about stock market. that's where all the good stuff happens. use investments at the beginning and begin to raise up your business or whatever you're going to do. as this is a very non-realistic idea, it's still worth the shot!