Time over budget alert
It could be handy to be alerted when a time tracked task runs beyond the time budgeted. Perhaps by a desktop alert of simply changing the system tray icon red and/or an alarm sound. This would be particularly useful for contract tasks where additional time spent cannot be charged for.
Ismael Rivera commented
I love the app for studying. If I could get a loud alarm that notifies me to stop playing guitar (after 30 min) and start studying math (1hr), take a break, then do some practice math problems, etc... A bathroom break (pause) button would be nice.
There is almost everything already available: an alarm, a budget per task, a timer counting time. All it needs is enabling alarms not only for times where tasks are supposed to start, but also for the time it is supposed to end because of exhausted budget. It just a small step for a talented programmer, but would open a myriad of additional use cases for the users.
With such a warning, budget limits would make much more sense as you'll certainly recognize when you come near the limit and when you cross the limit.