Star Defender http://www.deprice.com/stardefender.htm
DESCRIPTION Star Defender is a vertical scrolling space shooter and a spectacular clone of Space Invaders.
You are a test pilot flying Tornado. Your spaceship is controlled by your mouse. The ship is limited to movement in lower line of play area. Star Defender possesses all of classic features of genre: professional and vibrant graphics, breathtaking gameplay and an original soundtrack.
In game you're a star warrior wandering mysterious space worlds of an alien Galaxy. You're sent there to defend your world against invading horde of enemies. If you dare and you can defeat them all!
To fire, press left mouse button. If you have rockets - press right mouse button. Tornado can have up to 5 levels of power-ups. Each level gives you both more life and a more powerful weapon. Every time you are hit, you will lose 1 power level.