In my current job, I'm doing lots of workshops. I find time keeping can be difficult, so I was looking for a countdown timer online and couldn't find any that's big, easy to use, accurate and didn't have obnoxious sounds. So I made one myself! Big Timer is a full screen countdown timer for work stuff, like meetings, workshops and presentations.
Because it's for work I even took the effort to make it work in Internet Explorer. I had a lot of fun making this, learned a ton about modern web development. Right now, its features may look limited, but there are some nice things, like the + and - buttons that you can hold and set a duration super fast. It's all optimized for quick handling while staying focused on the participants.
I hope it can be of use to anyone here. Please let me know how I can improve it for your work context!