Craft & Oak - Beautiful, minimalistic custom map posters
Stellarium - Stellarium is a free open source planetarium for your computer.
Mapiful - Create & order custom printed maps of your favorite places
KStars - KStars is a Desktop Planetarium for KDE.
Grafomap - A map poster of your favourite place on earth
SkyView - SkyView is powerful, easy-to-use app that answers questions about stars, constellations, and more.