Heard this one second hand, but believe it to be true. Subject aircraft is a Decathlon not registered to a Mike anybody at this time, but may have been once, or perhaps just piloted by Mike.
Fellow called Mike is inbound to a controlled airfield in VH-MMM and the ATIS is Mike.
Initial call went, Approach, gidday this is Mike on the Mike in the Mike Mike Mike received Mike...request clearance.