Window Silhouettes: This is more of an indoor/outdoor decoration. Cut out popular Halloween shapes in black paper and adhere them to your windows. When the indoor lights are lit, the shapes will come to life.
Halloween tape ghost: wrap form, in sections, in packing tape. Sticky side out first then sticky side on top. Cut down the side and tape together at the join. Spray glow in the dark or use glowsticks inside.