WinExec

The WinExec application was designed to be a very small tool that is intended as a launcher for other applications via HotKeys.
Normally, when you specify a HotKey for an application it will only allow you to launch one instance of the application via the HotKey. Any further HotKey presses just result in the first instance becoming active. While this is great in many cases, it can sometimes be a real inconvenience.
WinExec allows you to work around this issue by specifying it as the application, and the real application as parameters to it. Since WinExec exits as soon as it has launched the application in question, subsequent HotKey presses will result in a new instance of the desired application.
An example says more than a thousand words they say, so here goes. Say you want to be able to launch several notepads via Ctrl-N. You would then create a shortcut to:
WinExec Notepad.exe
and then assign Ctrl-N as the HotKey for this shortcut.
If on the other hand you want to have each notepad open a certain file, youd instead create the shortcut to:
WinExec Notepad.exe "My textfile.txt"
Notice the use of quotation marks around filenames/parameters with spaces in them. This technique can be used for the name of the application as well as its parameters, e.g.:
WinExec "Some application.exe" /load "my config"