Thanks d-p, I'll check them out.

Ok, in the case of using color saturation to 100% tired immediately visible form and therefore use a white background to do so can damage your hearing (This is the reason why never work on a white background on screen), so use a background color is to work as visually(especially if you paint in pixels).

Nice car.
If youre planning to do an pixel art tutorial, you might want to check out the very cool tutorial by "cure" in the PJ Forum and my very old one about car avatars.

Thanks. I went and cleaned the rest of my pieces to transparent backgrounds (well, in the icon at least). 

But why do you say to always work with a colored background? Can you explain? There was also a guy who said never to use saturated colors above 70% and never use true white/black. Clearly I'm missing something, so I'd appreciate to hear the reasoning behind it.

Always try to work with a colored background, not white, some advice.

Much better!

OK, uploaded the transparent version + stripped one gray in the process.

Celestial as in space black/blue/galaxies background? 

I don't know. I like the white background. I always loved rendering 3D models with all around lighting (just ambiental occlusion) on white background. It has that gallery feeling with nothing distracting from the object itself. I think it looks great on pages like Tumblr, where it seems to bleed into the white background of the post itself, but I do understand it doesn't look best on PixelJoint as it's a dark themed site. I tried making a transparent version especially for here, but the bright reflections in the windows just don't make it seem coherent on a dark background.

Well, I guess I could have repainted the whole windows, hm, let me see ... <puts on Lotus The Ultimate Challenge Soundtrack>

I recommend using a more comfortable background see, like a celestial, as the white strains the eyes.



Pero nice sprite de LOTUS game!!
 

Memories of two Amiga's linked up with two players on each having a 4 player race on Lotus 2.  Good times.  Classic music too.

Nicely done. I loved and hated that game.