Details on the 2002 5k Contest can be found at www.the5k.org.
A full-functioned cross-browser DHTML API script under 1k with included documentation and a demonstration. Spawned a minor cult following and resulted in it's own subsite.
Zip around the solar system with this DHTML simulation. The sun, all nine planets, and all satellites discovered before the Voyager missions are included. All the relative distances and body sizes are roughly accurate as are the colors (I've chosen an average color for most of the planets). For simplicity, I've flattened all the orbits so that they are all in the same plane and I've made them all circular (so, for instance, Pluto's orbit will always be outside Neptune's).
When you start, you will be 3 billion kms above the solar system with your view centered on the sun. Move closer or further away with the Zoom control. How much you move with each click on the Zoom buttons can be custom set from 1 to 1 billion kms.
You can also rotate your view using the Rotate control. The up and down arrows rotate you around the x-axis while the left and right arrows rotate you around the z-axis (at the start, the x-axis runs left-right in the plane of the screen and the z-axis is perpendicular to the screen). This should allow you to get any view you want but in some positions, their behaviour can be counter-intuitive - a good sense of 3d visualization is handy.
You can also change the speed of time or even stop it and make time go in reverse.
Usually, your position will be with respect to the sun (ie, the sun will appear fixed in position). You can change this by selecting a planet from the Lock To dropdown. You will then start to follow your chosen planet. You can still move around but the whole system will behave like the locked-to object is fixed in space and everything will move around it.
Initially, all the moons are visible and all objects are labelled. You can turn off moons and / or labels to get a cleared view. You can turn them back on again at any time.
Should work in IE5+, NS6+ and Moz though it performs better in IE.
In IE, all objects are visible even if they are far away - you can turn off the labels and still see where things are. In NS and Moz, you only see those things which are close enough to be visible - turn on labels to see where distant objects are.
The gray cross indicates the center of the viewport. Line object up with this cross to zoom in to them without losing them.
Turn off the moons to improve performance - particularly in NS and Moz.
If, when zooming, your target object disappears, you probably overshot it. Back up, change the zoom value to a smaller one and zoom in again.
The easiest way to zoom into something is to, at the start, wait until it's orbit takes your object to immediately above the sun (where the orbit crosses the y-axis). Stop time and use the up Rotate arrow to move the object to near the gray cross then start zooming in. Adjust the vertical position with the up-down Rotate control and the horizontal position by changing the time to move the object along it's orbit. Once it's close enough, lock on to it and start time.