A large number of patents in the IT area appear to have a very similar diagram embedded int them somewhere, usually some forms of a block diagram detailing system components such as Northbridge, Southbridge, memory, disks, CPU and (this is my personal favorite) speakers.
These exist in patent applications even in cases where they appear to bear no relationship to the invention at all and, as far as I can tell, the descriptive area that describes them simply states that it's one possible system that may contain the invention.
Why is this necessary even in cases where the surrounding hardware is irrelevant? For example, why is amouse even mentioned in US8607238 when the patent is about "lock wait time reduction in a distributed processing environment"? I can't think of any rational circumstance where the mouse would be important here.
In addition, I've seen database-related patents mentioning audio devices (eh?) and irrelevant details such as the internal machine architecture (CPU/Northbridge/Southbridge), some of which doesn't even exist on some architectures where the invention may exist.