Set Value Of Cell Equals To Looping Value

Im using this to loop through ID's for my code.

Sub Test2()
' Select cell A2, *first line of data*.
Range("A2").Select
' Set Do loop to stop when an empty cell is reached.
Do Until IsEmpty(ActiveCell)
' Insert your code here.
' Step down 1 row from present location.
ActiveCell.Offset(1, 0).Select
Loop
End Sub

How can I set a cell value = to what cell I the loop is currently on?