Nice game.
"Original" and "Shooter". Two words that were fast becoming mutually exclusive due to the masses of shit released on this daily. But this IS an original shooter.
Ok fine, this isn't exactly ground-breaking stuff. The "move with the mouse, shoot to click, fancy particle effects" well has been drained so thoroughly that it will never again produce anything truly new and fresh. But it has a nice idea with the health-recovery-pixel-collecting, it's short enough to not get tedious, and it has a relatively large number of different ships to use.
And you used relaxing, slightly euphoric music, rather than the stomp-your-brains-out brand of shitty repetitive house... well, for argument's sake we'll call it music, that every other shooter flash game and their dog has used since the dawn of time.
The two largest flaws I can make out are as follows. Firstly, there is no way to aim without moving: you should make it possible to hold SHIFT or something to anchor your ship to the spot. Second, It would be good if you could change ships at checkpoints, to try out the ones you've unlocked: it would give the player a better sense of how their progressing, know what I mean?
Another minor flaw are that you can't mute the sound while playing (seriously, just make it so you press 'M' to mute. The best games are the ones that ask you before they even start if you want sound or not.). As a final note, the ad in the background was just a little bit tacky. Not too huge a problem, though... at least it was translucent.
All in all, a nice change of pace, but still nothing to write home about. Good game, next time try aiming for "amazing". Even if you don't make it, you should at least make something interesting.