Ramsophone - A generative art/music machine. (Be sure to refresh!)
Sortd - Rated the #1 App for Gmail
Generative Art in Go - Learn the basics of algorithmic art with the Go language
KanbanMail - A Kanban board for your emails.
Big Art - Discover street art
Trello - Infinitely flexible. Incredibly easy to use. Great mobile apps. It's free. Trello keeps track of everything, from the big picture to the minute details.