Selling a side-project. Any advice?

Hey HN.

I recently put up a side-project for sale (details here: http://simondlr.com/post/63455198178/twimemachine-for-sale).

I'm trying this approach before I head to a marketplace such as Flippa. I need advice. Some questions that come to mind. Do I approach specific potential clients? Is a marketplace such as Flippa ideal? If you have any experiences to share of selling a side-project, I would love to hear it!