This is a great game for everyone who enjoyed Space Invaders back in the 1980s.
One of the more entertaining games with an online highscore list.
DO NOT PLAY THIS GAME IF YOU HAVE A JOB AND CAN'T STOP PLAYING UNTIL YOU MAKE IT FIRST ON THE HIGHSCORE LIST.
Actually I wished that feature could be turned off because you tend to be obsessed about beating someone's record rather than just enjoy a little distraction. (-1 point in features)
Each level is followed by a list of items to buy. If you earned enough money shooting space ships or collecting special items (dropped bonuses, bailing aliens, destroying falling wrecks) you can choose power ups for shield, gun power, extra bullets, smartbombs, addons or ship speed.
Full-screen mode with a resolution switch is possible and does not relocate windows or desktop icons when you leave it. Aspect ratio stays 4:3 even on 16:10 displays. (-1 point for graphics & sound then)
Controls, music volume and effects volume are configurable.