Its the Basic Instrument Flight Module.
The IR is split into BFIM (Basic Instrument Flight Module) and PIFM (Procedural Instrument Flight Module).
The BIFM is 10 hours (5 sim) and gives a 10 hour reduction in both the IR and CPL. As far as I can make out it doesn't require a test and gives you a certificate to show you have completed it. I'm not sure whether it has any worth on its own though.
I am trying to do my training around work so any way of breaking it up is good for me.
There seem to be schools offering this in Europe but I have not found any in the UK.