Might seem odd to put a bat in the macro section, but...
this is the Western Pipistrelle; the smallest bat in the US. Most references indicate a body length of about 65mm, or 2.5". This one was even smaller, so it may be a newly weened pup. After taking several shots, I attempted to photograph my index finger next to it for size perspective, but it flew off. It was no longer than 2" in length. Adults weigh 5g; the same as a US nickle.
These shots were taken in the dark, on a ladder, with a 5DIII, 100mm f/2.8L, and 580EXII with a diffuser. I had to use Auto focus, and the AF-assist beam from the Speedlite. I'd say the combo nailed focus pretty well. 
1.
DW0A5540_960x
by ...moose..., on Flickr2. This shot was taken about 7" away (working distance).
DW0A5543_960x
by ...moose..., on Flickr3. Cropped, tone-mapped, to show details in the face.
DW0A5543_TM_960x
by ...moose..., on Flickr
