Interactive mapping tool for GPS, waypoints, georeferencing images

Hello!

I am looking for an interactive mapping tool (Windows or Java) which is
able to
- import and plot one or more (!) GPS devices (COM ports or even TCP/IP
ports as source)
- plot tab separated ASCII data files with positions, and other
information
- import and plot images (e. g. JPEG, PNG, GIF); they should be
georeferenced by clicking on two known points on the map and entering
their coordinates.
- setting waypoints

It would even be great if it had some typical GIS features like
querying and importing some other GIS formats like ESRI Shape.

There are a few tools which may plot one single GPS. Perhaps it could
be done by integrating other software, too. If the GIS would read the
tail of a lat/lon ASCII file every few seconds, other programs could
deliver the data to that file.

Do you know of a tool like this?

With best regards,
Johann