Spacechart is a program to display 3d maps of stars and move freely around it. It is capable of showing only a subset of the stars in a given data file, and only those within a given distance of the center of the display. Also, it shows lines between stars that are closer than a given distance.
Web : http://spacechart.sourceforge.net/
spacechart is already packaged in the main Debian archive: spacechart
Comment -- There's another package with a similar aim: Starplot, but I really like Spacechart a lot. I imagine it could become more than just an executive toy in future. This is one of the great things about a Wiki: its ability to provide the meta-information that so many users need to get themselves oriented.