Windows Time Bomb is an easy-to-use application that will enable you to schedule it to launch any program you want. Set your time to open a file or launch an application and start timer and WTB will launch it for you.
Windows Time Bomb is freeware.
not exactly a beauty, but not as ugly as WTB:
The main feature of TimeLeft is a powerful customizable reminder, which can show a message, play music (any formats including mp3) or open a link, document, execute an application, turn off your monitor or shutdown your PC.
TimeLeft is freeware.
and here's one with command line funtionality:
Countdown Clock for Windows
This useful utility allows you to count down time with an alarm. It's great when needing a countdown timer to be reminded of a specific event such as checking the roast cooking in the oven, checking the water level when filling your hot tub, or what ever else you can concoct. Supports up to 720 hours in the countdown.
With Countdown Clock you can:
Play any multi-media file including movies, music or sound files when the counter gets to 00:00
Launch any program of your liking when the alarm goes off including programs that will shut down your system.
The clock can be hidden in the system tray.
The clock can be resized to virtually any size on your desktop including FULL SCREEN.
Instructions for passing command line arguments:
countdown HH MM SS Y "Media file" "File To Run"
Countdown Clock is shareware, try before you buy.