select within aggregate?

Hi!!

Of course the following is possible in various ways but i wonder
if there is an elegant and simple solution:

A part from apache log:
remote_host varchar(50)
request_uri varchar(50)
ts timestamp with time zone

Now i want to see which host has done how many requests. This
is not difficult:

SELECT remote_host, count(*) FROM apache_log GROUP BY remote_host;

But now i would like to add a column to the result which
shows the most recent requested uri for each group.
This sounds quite easy at first glance but i see no simple solution.

I suppose with max(ts) i could acquire the time of the
most recent request within the group, but how do i get
the corresponding request_uri without doing subquerys or
something like that?

Thank you very much!

Klaus