Though I don't have a solution to "Exact", there is an approach to getting back to the same cell that you were at. This is to tag the cell with a unique CellTag and then search for that CellTag using NotebookFind. Once found, you can then do a SelectionMove to Before the Cell or After the Cell. (Also before doing such a move you generally should remove the cell tag just for good housekeeping.) I am fond of tagging... See

http://library.wolfram.com/infocenter/Conferences/7246/

from some while ago.

I can partially answer your second wish, you can scroll to some places :) with FrontEndTokens:

FrontEndTokenExecute[EvaluationNotebook[], "ScrollNotebookEnd"]

other that seems to be relevant:

{"ScrollLineDown", "ScrollLineUp", "ScrollNotebookEnd", 
"ScrollNotebookStart", "ScrollPageBottom", "ScrollPageDown", 
"ScrollPageFirst", "ScrollPageLast", "ScrollPageNext", 
"ScrollPagePrevious", "ScrollPageTop", "ScrollPageUp"}

There does not seem to be a ScrollPosition option for Notebook. And hunting around in various other places there does not seem to be something that is equivalent. I wonder whether there is a means of using CurrentValue in someway to get at this. But, if not, then this is a very sensible suggestion to pass on to the developers because this is clearly a form of control of the notebook that should be in the system, and should be an option to Notebook.

Do you mean this?

Dynamic[MousePosition[]]

Paul.