Suggestions for Time-Tracking Apps?


I am tired of time always getting away from me. I can start a task that I think will take 10 minutes, and before I know it two hours have passed! I have been searching for an app that will make my phone alert me to the passage of time, preferably without any input from me. I was thinking of something along the lines of an alert every hour, like an old fashioned clock would do. I have found plenty of apps for alerting me to deadlines, and some that I can program to start a timer when I start a task, but that's not quite what I'm looking for. Suggestions?