PowerShell One-Liner: Strings to Arrays and Back Again

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.

PS> $home.split("\")
C:
Users
timid

And the other way around.

 PS> [String]::Join("|", $(gci))
Contacts|Desktop|Documents|Downloads|Favorites|Links...

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').