How to view the activity of postgresql

I want to see what statements are being executed on a remote postgresql
server, ideally in a scrolling display in some gui tool. In MSSQL, there
is a profiler application that gives this.

The best I've found so far is to set postgresql to log to a csv file &
then use pg_read_file to periodically read the log file & display it to
the user.

I've written a little tool that does that:
http://www.xentu.com/pgprofiler/

However, it seems a very akward way to achieve what I'm looking for and
will probably slow the server with all the file reading & writing
involved.

Is there a more efficient way of doing this?