I've added some productivity hacks over the last several months. Here are 5 that have been working well for me lately:

File, Do, Defer. I've started using the "file, do, defer" system. I look at a task (in Wunderlist, a great to-do list manager) or an email in my inbox and decide if it needs action or not. If it doesn’t need action I either delegate it or file it. If it does need action and takes less than 3 minutes, I do it. If it will take more than 3 minutes I’ll defer to a time when I have more bandwidth and focus. To keep me focused on the 3 minute rule I’ve begun using the Pomodoro app for Mac that tracks the time I spend on a task. This isn’t to make me rush through the task it’s to make sure I stay focused on it and get it done quickly and don’t get distracted.
Working Offline. I’ve been doing this for years and can’t recommend it enough. I put my email in offline mode, close Slack and focus on initiating rather than responding.
Virtual Assistant. I’ve hired a virtual assistant for personal tasks. There are lots of great services out there but I use FancyHands which has been great. My virtual assistant does everything for me that I don't want to do -- they have have coordinated my move, found me a couch, helped plan a vacation, changed my cable service, researched health insurance plans and booked a New Year's Eve dinner reservation. I’m constantly scanning my to do list and looking for low-value tasks that I can outsource. It's low cost and a massive time saver.
Soylent. I’ve begun drinking Soylent, a meal replacement drink that supposedly contains every nutrient needed by the human body. It’s fantastic. It allows me to have breakfast on the go and sometimes lunch on the go so I can maintain energy with zero time commitment. It’s incredibly helpful on hectic days.
Make projects seem small. We all have those projects or tasks that need to get done but seem hard and time consuming and stressful and keep getting put off. I read about a productivity trick in the book Getting Things Done to help deal with this problem. The trick is that you think about the thing you need to do that you keep putting off and on the bottom of a piece of paper you write down the outcome that you want with regard to the project -- e.g. what is success? Then break it up until small tasks and write those as a list on the rest of the page. Going through the process of breaking the project into small tasks makes it seem so much easier and actually gets you somewhat excited to go do it.

Hope some of these are helpful.