May I suggest that you try approaching your ideas from a slightly different perspective: pick those that stem from a personal pain point, that way, you'll be personally vested.

Whilst it's exciting to come up with novel ideas, nothing's more spurring than fixing and making your own life better.

To illustrate, here are some projects that I've embarked on, which scratched a personal pain point and went on to be incidentally well liked by others enough to even pay for:

http://freshlog.com

I had to submit bug reports with attached screenshots in Basecamp (later Pivotal Tracker and Fogbugz), which involves many steps, so I made this.

http://screendocs.com

Customers were frequently asking how to do something and nothing beats sharing a webpage with step-by-step screenshots. Later I found Dropbox to be a great medium so I integrated with that.

http://handpick.me

I felt that Facebook was a little too noisy and public to share personal links with my family and friends, so I made this.

http://letsrecap.com

Whilst reading long articles, I'd want to select some text, mark it out and jump back between them easily.

Whilst these are not runway successes with millions of dollars of profit, it certainly helps you build up the stamina to successfully ship and launch projects.