Google Chrome Extensions

Chrome Clock

To set the alarm time, click on the toolstrip.

In the first field enter the hour of the alarm time, press Enter to go to the second field and put the number of minutes there.

Press Enter one more time and the alarm is set.

To cancel it at any time, click on the toolstrip.
To set a timer, click on the clock, and click on the “A” button to switch it to “T”. It is not too precise now, just waits until (current_time+timer) will be reached.