Chrono allows you to create a timer in seconds and shows the remaining time in your menu bar. Great for time boxing or general purpose timers to boost productivity. There’s also a log where you can analyse how you’ve spend your time.
Clockey lets you add the time from as many timezones as you want to your menu bar. Quickly access any time zone with one click.
The menu bar app Coffee is a tiny time tracker. You can track multiple projects, start and stop tracking your time with a single tap, and export data to CSV for invoice creation.