1 - Notify me when Movie tickets are available to book. Used google scripts that run every minute and hit a URL to check if tickets are available now.
2 - Book a class when it's available, I have joined a Gym where you have to book a class before going, and the Zumba is very famous there the time it opens it fills up in 30seconds and there are limited seats, so if you are late it's gone. I wrote a script that checks and books the slot for me and then adds the same in my calendar. I extended the same using google forms when I want to book another class at some specific time which is currently not available if somebody cancels it will be available. The script keeps on checking until class start time, if available books and notify me.
3 - In my team, everyone plays Foosball and after lunch, it's everyday discussion who will play first and with whom. I wrote a script which will decide the matches and players in each team. I used the google app engine to deploy it, which is still running and just by hitting the API will sort the things for us.
There are a few other automation I did using IFTTT.