Boomerang shaped object or light traveling extremely fast in Lisbon, Portugal.At aprox. 1:04 AM, Lisbon time, GMT+0, i was going back home in my car after leaving my girlfriend at her house. When i was passing through a dark road, which i pass everyday for the past 6 years, i noticed something in the sky. It looked like a spotlight, but boomerang shaped, it was going fast, like some kind of light was being projected in the sky. The sky was cloudy, so it really looked like a light projection, either from bellow the clouds or above them.I didn't pay much attention to it as i thought it was a reflex or something like that. However after 50-100 meters i saw it again, this time going on the opposite direction (from right to left) with the pointy part of the boomerang always facing the direction the object/light was taking.I started to look at the sky to check exactly what it was. I didn't see it for a while, but then saw it again and again. I saw it around 6 times, being the last one near a roundabout, aprox. 300-400 meters from when i saw it the first time. Most of the times it was going from left to right but i saw it at least twice going from right to left.The light was traveling extremely fast and going on both directions randomly. The size of the object was like a big sized plane at the minimum altitude. However i didn't hear any sound.