Dynamic paging/scrolling with a DataGridView

I was thinking of creating a DataGrid that will query for results as the
user scrolls. I realize I would have to know how many rows would fit in
the visible area and what rows to show based on the location of the
scrollbar etc. I was wondering if anyone else has done something
similar and maybe direct me to an example. Also have you found it to be
a practical alternative to paging.