I often get searches for blank sky maps, so I thought I'd do just that. Problem is, how blank, in what coordinate system, and in which projection. See, there are quite a lot of knobs to twiddle. So let me just give a few examples here. Suggestions/requests are welcome.
First: Equatorial coordinates, in Winkel-Tripel projection with coordinate grid on white background. Projection-wise, probably the best compromise between length- area- and shape-distortions that come inevitably with every map projection.
Galactic coordinates in Mollweide projection. Nothing better than Mollweide (or Hammer-Aitoff, see below) for galactic maps, with the origin, i.e. the center of the milky way, right in the middle.
Ecliptic coordinates, this time on a black background, with the simplest of all projection, equirectangular, thats, really just a linear mapping of coordinates to area.
And something completely different, supergalactic coordinates in Hammer-Aitoff projection. The supergalactic plane is the one in which the local filament of galaxy clusters seems to be oriented, visualized here with all galaxies brighter than 12th magnitude in red.
Stellar data from the Hipparcos catalogue, with stars down to magnitude 7 shown, galaxies from the handy Saguaro Astronomy Club Database, and map projections according to USGS's fabulous Map Projections: A Working Manual by John P. Snyder. And milky way data from PP3