Flying pests that look similar to mosquitoes. Even though these things don't bite... the sheer numbers of them in one location can be extremely disruptive. Midge swarms have even been known to cause disruption to traffic and can also appear on weather radars.
Most commonly found near streams, rivers, ponds, and large bodies of water. Usually dormant until spring and early summer weather.
Jeff's entire house was covered in midges... you couldn't even tell the house was white.