Starting PowerShell scripts in parallel

I need to create a script to launch more Powershell scripts to run in parallel.
Looking around the blogs I found some solutions based on the creation of Runspaces, but up to now I was unable to make any script work.
Is there any sample I can start from?
Is there any other solution I can implement?
Regards
Marius

https://github.com/proxb/PoshRSJob