For VB6, here are a couple of samples

For just one type of control:

Text1.Tag = Now
Text2.Tag = Now

Dim myControl As TextBox
For Each myControl In Me.Controls
   myControl.Text = myControl.Tag
 Next myControl

For ALL controls: (Use TypeOf to distinguish specific control-type)

Text1.Tag = Now
Text2.Tag = Now

Dim myControl As Control
For Each myControl In Me.Controls
   If TypeOf myControl Is TextBox Then myControl.Text = myControl.Tag
 Next myControl

This won't work correctly for VB.NET, though, since they enforce Control-ownership differently: child-controls won't be included in the collection

For VB.NET 2002, I use this procedure to set the ToolTip of all applicable controls to display the maximum length by calling the procedure and passing the form (yes, the form!) as the first parameter and a ToolTip object as the second; just remove the second parameter to fit your needs

   Public Sub SetFormControlsTooltips(ByRef myControlsCollection As Control, ByVal myTooltip As ToolTip)
      Dim myControl As Control
      For Each myControl In myControlsCollection.Controls
         If TypeOf myControl Is TextBox Then
            Dim myTextBox As TextBox = DirectCast(myControl, TextBox)
            If myTextBox.MaxLength > 0 Then myTooltip.SetToolTip(myControl, "Max Length: " & myTextBox.MaxLength & " char(s)")
         End If

         If TypeOf myControl Is GroupBox Or TypeOf myControl Is Panel Then
            Call SetFormControlsTooltips(myControl, myTooltip)
         End If
      Next
   End Sub

usage:
Dim ttpToolTip As New ToolTip()
Call SetFormControlsTooltips(Me, ttpToolTip)

Notice the last If-Statement, which calls the same procedure but with a different object this time, which is a containter object


Hope this helps!