Holy diety, this is severely cool. If only there was a desktop version...

Some desktop image editors let you do this, although usually with a less user-friendly interface. Inkscape (free) does this (.svg export), and Xara Xtreme (cheap and worth the price) does it too. I'm not sure how the results compare to the online tool for logos, but they are quite good for photos.

I've always been fairly disappointed in every 'vectorizing' tool I've tried. I have yet to try this one but the examples look incredible.

Frickin' awesome.

this honestly isn't that spectacular. I have coded stuff like this in my spare time.