Well, not always, but many months ago when one of my supervisors was telling us about the SEM (scanning electron microscope) that the lab was purchasing, he mentioned that it was strong enough to "see up a mosquito's ass."

Therefore, when the time came for me to attend the training for using said way-cool electron microscope, I, of course, asked if we could look up a mosquito's ass. To the instructor's great credit, he didn't bat an eyelash at the request.

So, once we finished up the basics of how to operate the scope [note: the basics take a few hours to learn. Actually getting proficient and good at operating the scope probably takes about a year of steady use.] we went scavenging for bugs. A windowsill yielded the following specimens up:

This is the eye of a small fly:

This is a closer eye of the same fly:

Then we moved on to a mosquito carcass. After we looked at it under the scope we realized that it was pretty dessicated (hence the sunken-in eyes) and kinda dirty.

This is a picture of the end of its proboscis, i.e. the part that sticks you. (All of the debris that you see is dust that it collected while being a corpse on the windowsill.)

And, finally, this is a view up a mosquito's ass: (Again, a ton of dirt and debris that was not noticeable until looked at under 1320 times magnification.)