The RCP downloads are meant as a base for building Eclipse RCP applications.  
As such, they do not include an application of their own and simply running the 
RCP install will do nothing.

Warning: The HPUX PA_RISC build machine is currently offline pending upgrades,
therefore the SWT Motif HPUX PA_RISC libraries could not be recompiled. We
recommend that you do not use the Eclipse 3.3. for HPUX Motif from this build.