CoolCoderSJ is one of the lesser known Repl.it users and Repl.it Discord members.
He has built his own URL shortener with more features than bitly - get it here.
He has also built a QR code generator. (Under maintenance)
He has a Python tutorial here.
He loves building anything with python, and loves jams.
He recently built Reflux Marketplace, (here), a place to share reflux themes with each other. It has 18 themes as of now, including all of mat's themes (minus 1 or 2) ported to reflux.