Some things to make you stop and stare ...

[warbirds]

Things that make me smile;

Control cables to the tail surfaces on Moth vibrate

Clouds move and change shape constantly like real clouds

The feeling of really being high up when looking at the ground

The way the planes drop altitude when power is off, most sims leave you floating when power is off

The really great and detailed and easy FMB

The way the front crew member moves when you slip the Moth

The early morning or late day lighting and shadows

Many more to come I am sure.