[DigitalSid]

Originally Posted by Jesus.

Without wishing to be too Charles Darwin, it was unlikely to be a flying ant, and more likely to be a simple house fly.

Maybe it was a fly pretending to be a flying ant?

Flying ants are common, a percentage of most species are winged, they're produced when a colony has enough workers, so they can leave an establish their own, you see them most hot summers:
http://news.bbc.co.uk/1/hi/magazine/7525028.stm