Hacktoberfest, an open-source Hackathon, has selected its top ten favorite projects across five categories for the year 2021. These include Best Overall Project, Most Visually Pleasing, Most Technically Impressive, Best Mobile Project, and Most Spooky/Fun. The winners will receive a limited edition gold medal shirt, while all participants will be awarded a limited edition participation tee. Hacktoberfest encourages developers to contribute to their favorite projects during the second half of the event.