Authentication - Where To Store The Username Of Logged In User

When a user log into my asp.net site I use the following code:

FormsAuthentication.RedirectFromLoginPage(userid, false);

As I often need to use the userid I can then later get the userid by:

string userid = System.Web.HttpContext.Current.User.Identity.Name;

Now I also want to show the logged in username on each page and my questions is therefore where do I place the username best if I need to use it on every page. User.Identity.Name is already taken by the userid so I can't use that one. Another solution would be to get the username from the database on each page, but that seems like a bad solution.