What language’s writing system looks especially cool to you? Whether you think it’s the most beautiful, or if it just catches your eye and you think it looks neat, whether or not you can understand what’s written?
I think the Inuktitut language looks really cool. Here are the letters, and here are samples of things written in Inuktitut.
Traditional Chinese characters, for me. I never get tired of just walking down the street reading them.
I’m partial to both Armenian and Georgian.
Arabic … looks like art or something
Farsi is a beautiful language
It often is.
I’m going to go with Japanese. Yeah, many similarities to Chinese but I think the art form is taken to a new level in Japan. Of course, that assumes the OP is talking about calligraphy as opposed to, say, “newsprint”.
I think Thai and Hindi script are both beautiful.
Indeed, I think Georgian is unbeatable in purely aesthetic terms. A friend of mine is a Georgian language teacher and I could watch him write for days 
Wow, Georgian is really cool. 
I don’t think I’d seen it written before.
Javanese. (Scroll down for script images.)
Ancient Egyptian Hieroglyphic and Classic Mayan Glyphs. If I had to choose, I’d say Mayan is overall cooler.
That and Quenya in the ómatehtar mode of Tengwar, of course.
I really like Arabic and Hebrew.
I was going to say Javanese. I’ve never seen anything so elegant and graceful.
I encountered it long ago, in a graphic design book showing how public documents and announcements were laid out in various cultures. The Javanese example simply took my breath away and I’ve never forgotten its impact.
Burmese looks good. All the circles give it a sense of unity.
And I like the way the lines connect letters together into words in Sanskrit.
That is the most alien-looking human language I’ve ever seen.
French looks the prettiest, but German is the coolest.
The Burmese is gorgeous.
Also Thai and Arabic.
ETA: Many years ago I had a classical piece of music (Borodin’s On the Steppes of Central Asia) tattooed on my upper arm in memory of my father. Over the years it’s blurred somewhat from sun exposure but I still get a lot of compliments on it. Now that it’s not instantly recognizable as a piece of music, I’m often asked if it’s Arabic.
I have to admit that I’m oddly fond of Hangul script.
Then, there’s that certain aesthetic mystique about Voynichese.
