I couldn't keep up with it but http://lift.do/ has a habit streak and motivation by seeing other people keeping on tasks.
Depression comes from not keeping up on tasks and losing your streak. That's when you start questioning yourself and the cycle keeps happening. There is definitely a niche need for a mentoring / motivational network for depressed people. This whole thread, and your last one, plus the momentum that came with them is proof.
"Depression comes from not keeping up on tasks and losing your streak."
I think you mixed up cause and effect. Depression mostly leads to not keeping up with what you're doing, which is the starting point of a downward spiral. Depression isn't "solved" by motivation. Depression is complex, but most times a common source is a overwhelming emotional event, which is re-felt in every down turn.
I was once asked what I was doing to live up to a certain person's life with whom I was associated. I said I was doing what I could for myself today so that I could do anything at all for others in the future.