Start a timer in seconds, try the Pomodoro technique or just looking for a (world)clock in your menu bar?
Check out these Mac Menu Bar Time Apps:
Collection:
Time Apps
Alarm Clock Pro
You can use Alarm Clock Pro fot almost everything. For instance to ping web pages, launch URLs, open files, erase folders, execute shell commands.
But also when waking up, as a reminder to take medications, keep social appointments, or schedule follow up appointments with clients.