[Suicide Junkie]

The Wormhole Beam will randomly teleport the ship it hits anywhere on the combat map.

It works best to break up enemy formations, so your fleet can take on the enemies one at a time.

The tectonic bomb allows you to totally destroy a planet, leaving only uncolonizable asteroids behind.
If you use a tectonic bomb in combination with a matter gravity sphere (planet creator) you can destroy and rebuild planets until they turn up as a breathable atmosphere.

As for Warppoint openers, 100 LY is 10 squares on the galaxy map.
If you right click on the galaxy map, you should be able to turn on distance view, and it will give you the distance of every other system from your currently selected system.