Grafomap - A map poster of your favourite place on earth
OpenSpace - OpenSpace is open source interactive data visualization software designed to visualize the entire known universe and portray our ongoing efforts to investigate the cosmos.
TiltMaps - Create map posters of your favorite places & memories.
Celestia - Real-time 3D visualization of space
Craft & Oak - Beautiful, minimalistic custom map posters
Stellarium - Stellarium is a free open source planetarium for your computer.