move a form by clicking anywhere on the client area

1. insert the following line into your form's "Private declarations" section (message handling procedure declaration):

 procedure WMNCHitTest(var Msg: TWMNCHitTest) ; message WM_NCHitTest; 

2. add the following code into the "implementation" section of your form's unit (where Form1 is assumed form name):

 procedure TForm1.WMNCHitTest(var Msg: TWMNCHitTest) ;
 begin    inherited;    if Msg.Result = htClient then Msg.Result := htCaption;
 end;