I live near Duboce Park in San Francisco:
Every SF Muni streetcar line runs within walking distance of my house, but they all stop in different places. I can't wait in one place and be sure to catch the next train that goes past.
I used leave the house and hope that I wouldn't have to wait too long for a train to turn up. I'd often get to Duboce Avenue just in time to see a train disappear into the tunnel. I'd then end up waiting 10 minutes at the corner of Duboce and Church for the next J or N, wondering the whole time if I should walk to Church station and catch a K, L or M.
That got a bit much for me, so I made this:
It puts arrival information for all the stops near me on one page, and puts the emphasis on when I need to leave the house to catch a train. It tells me whether I need to get going right now, or whether I have 5 minutes to play with my kid before leaving.
I've had a beta version running for a few weeks, and it's completely changed my mornings. I'm getting to work earlier and a lot less stressed.
As the about page says, if you live exactly 6 minutes from Sunset Tunnel East Portal, 8 minutes from Duboce and Church, and 10 minutes from Church Station you may find it useful too.