When it comes to the BP versions before v.7, AutomateC.exe can be used for starting processes/schedules, which enables some nice options for "dynamic" triggering. Version 7 should have some native API options, which could be considered.
For example, if a process takes its input from an email message, Outlook can be configured to run a .bat -file (which contains AutomateC -command) when a specific email is received.
Or if a process needs to be started when a new file is added to a shared drive -folder, it is possible to create i.e. a PowerShell -script which will trigger AutomateC -command, when a new file is added to the target folder.
And it is possible to even create scripts to trigger schedules when a file is added to a SharePoint -site, but things like that would be much more complex to do compared to the two examples above.