A hypothetical situation
 

Suppose someone lent you around $5000, with the stipulation that you pay it back in full within 30 or 60 days. How would you invest it to make as much money as possible?

if you know what your doing, stock market, if you don't, then don't borrow it, 1-2 months isn't a lot of time to do much with 5k.

Does this look like a scam to anyone?
http://www.invest2double.com/index.html

Is there any interest associated with the $5000 loan?

As far as the website, yeah it looks like a scam.

pyramid scheme.... first ones in get paid, last ones in get left holding their nuts.