1..300 | foreach {Write-Host " " -BackgroundColor (Get-Random 'Black', 'DarkBlue','DarkGreen','DarkCyan', 'DarkRed','DarkMagenta','DarkYellow','Gray','DarkGray','Blue','Green','Cyan','Red','Magenta','Yellow','White') -NoNewline}

#Revised this code after got help on facebook.
1..300 | foreach {Write-Host " " -BackgroundColor ([ConsoleColor].GetEnumValues() | Get-Random) -NoNewline