Process Stalker makes custom process monitoring easy by allowing you to select any running processes on a system, mark them and check regularly that they are running. You can truncate the length of process command lines to identify unique processes that you want to confirm are running when required. Process Stalker can be scheduled using the Windows Task Scheduler and can send an e-mail notification when processes are not running. This is a very simple but very powerful monitoring tool. In the free edition checks can only be run manually. All features are available in the full version.
Currently monitors: no processes selected, processes not running, processes with change command line parameters.