Create Sharepoint Online Site

New-SPOSite.ps1

#
# Need this
# http://www.microsoft.com/en-ie/download/confirmation.aspx?id=35585
#
Add-Type -Path "c:\folder\Microsoft.SharePoint.Client.dll"
Add-Type -Path "c:\folder\Microsoft.SharePoint.Client.Runtime.dll"

$siteUrl = "https://tenant.sharepoint.com/sites/things"
$credentials = (Get-Credential)
$ClientContext = New-Object Microsoft.SharePoint.Client.ClientContext($siteUrl)
$SharepointCredentials = New-Object Microsoft.SharePoint.Client.SharePointOnlineCredentials($credentials.UserName, $credentials.GetNetworkCredential().Password)
$ClientContext.Credentials = $SharepointCredentials

$webCreationInformation = New-Object Microsoft.SharePoint.Client.WebCreationInformation
$webCreationInformation.Url = "site1"
$webCreationInformation.Title = "Site 1"
$webCreationInformation.WebTemplate = "STS#0"
$newSite = $ctx.Web.Webs.Add($webCreationInformation)

$ClientContext.Load($newSite)
$ClientContext.ExecuteQuery()