Options for zooming plots other than zm()

Hi,

I am making some plots with plot() which have a fair number of points
(thousands) and I would like to be able to interactively select a
region of the plot and zoom in on it. I tried the zoom package which
has the function zm() but I found that it was unworkably slow to
refresh the display. I guess I can set the x and y range via xlim and
ylim but I was hoping to do it interactively. Does someone have a
suggestion for that?

I looked at ggplot2 but I wasn't able to find something about
interactive zooming, only noninteractive via plot limits. Perhaps I
have overlooked something there?

I have searched the mailing list archive and web pages in general but
I haven't found anything other than zm(). Thank you in advance for
your help, I appreciate it very much.

best,

Robert Dodier