I'm (just) a old-school Perl hacker and miss their join() and split() functions. Turns out, while PowerShell doesn't have them, .NET does, to a point.
And the other way around.
PS> [String]::Join("|", $(gci))
I always forget about the class methods.
The <[string]>.split(char) isn't as powerful as Perl's. We can't split on RegEx, though we can specify multiple delimiters as an @('a','r','r','a','y').