About 1: all of your experiences still hold today. A friend of mine started a file hosting business on the side when he was still in elementary school. Much like yours, it quickly became popular in one small community, and then spread out of that. Today, 8 or so years later, he has quit to work full time on it and he works on it... a lot.
"Easily scalable" only works to a point, then it quickly becomes expensive unless you create a solution tailored specifically for your problems, at which point you're negating the "easily" part again.
"Easily scalable" only works to a point, then it quickly becomes expensive unless you create a solution tailored specifically for your problems, at which point you're negating the "easily" part again.