Impersonation in SharePoint 2007

In SharePoint 2003 there was no easy way to use impersonation. In SharePoint 2007 there is a nice and easy build in way to use impersonation:

SPSite site = new SPSite("SiteCollection_Url");
SPWeb web = site.OpenWeb();
SPUser user = web.AllUsers["User_Name"]; 

SPUserToken token = user.UserToken;
SPSite impersonatedSiteCollection = new SPSite("SiteCollection_Url", token); 

You can also check whether an SPSite object is using impersonation:

SPSite siteCollection = SPControl.GetContextSite(HttpContext.Current);
bool impersonating = siteCollection.Impersonating;