Business venture for extracurricular activity?

<p>I thought of IMO a great idea for a web site several days ago and I’ve been working on it since. College admission is by no means the main motivation for me to work on this project, but if I am passionate about it enough can it serve well as my only extracurricular activity? I am applying to Cornell and Columbia University. </p>

<p>I won’t say what the site is but it involves user interaction and relates to my major. Working on it is my only extracurricular which is why I’m a little concerned.</p>