For example, let's say I've amassed $5 in the "Double My Money" fund and there's going to be yard sales in my community one weekend. I could take $3 of the $5 and buy a 12 pack of whatever soda is on sale that weekend for a quarter a can, put it on ice, and sell it for 50 cents a can. I would recover my $3 investment and would have made $3 more, growing my fund from $5 to $11 in a Saturday morning.
When the fund grows to say $1,000, you could invest in a mutual fund, put some money into a certificate of deposit, etc. Anything to keep it growing. And, of course, keep picking up change!
I think the point to this whole project is that most of us think we don't have enough to do anything with, when in reality if we just picked up enough pennies we would all be millionaires!
The truth is the little things we do every day really do count!