Below are a few ideas for the future...

• Pre-built Levels
• Asteroids (static items with gravity)
• Moons (dynamic/orbiting items with gravity)
• Magnetic Fields/Antigravity (pushes items instead of pulling them)
• Atmosphere around planets to create drag when close
• Landing angles (ie. burn up if you land by falling straight down onto a planet).
• Wormholes (teleport you from one part of the level to another)
• Level Editor
• Changing Backgrounds