Web-based Planetariums
SkyView Cafe
, very nice!
Your Sky
, an online planetarium from John Walker
StarMap
from Mt. Wilson
Starchart Map Server
Skymaps.com
, Free, high quality sky maps each month in PDF format
Planet Finder
, a Java applet
BinoSky
Java star chart program
by Akkana Peck
MyStarsLive
, an online version of
MyStars
Space@home
Horizons
, an ephemeris generator from JPL (best accuracy)
Solar System Simulator
from JPL