Define strange.
I've seen some odd stuff, probably the oddest was what could only have been the exhaust of an F-117 (only thing shaped like that around the back of the engine). Not super odd, except this was over VERMONT! Nothing up here for them though.
Add into that a couple really cool coloured meteors (green, red), a meteor that bounced off something (had a nearly 90 degree turn in it's trail), amazingly bright auroras, general oddities that are probably (HOPEFULLY) just optical illusions. In flight refueling- thought I was watching a mid air at first, watching the lights. And bats courting under a full moon, that was amazing.
Stangest and scariest thing I've ever heard- racoon love. Wow, sounded like someone being murdered with a sausage grinder or something. I think I spend the next hour clinging to a cloud, refusing to come down and play with the psycho killer, the first time I heard it.
Why, what have you seen Wildman? I'm a big believer in UFOs, particularly the Unidentified part.

I know what I don't want them to be, I don't think we're ready for that yet as a society. But I also accept that there is a small number of sightings that can't be given a logical explanation. *shudders*