Am out camping, and was taking pictures of the night sky, originally thought of this one as ruined by the fireflies, but then I thought of this contest.
It's hard to see but the bank on the opposite side of the lake is covered in tens of thousands of them, and a few landed on me during the exposure. Emailing this from the wilderness tethered to an iPhone 4.
Canon T2i, @ f/4 ISO-1600, 120s, 17mm, 17-85mm EF-S IS USM

-Jeff Sondag

I shot this with my NikonD80 on the Bulb setting. I had left the shutter open for a minute and a half to capture this image. It was taken on a hot Summer night in Fairfax around the back of my boyfriend's house. There were probably more fireflies that night glowing up the bamboo trees in the yard than ever before or since. I'm glad I went out there when I did because just yesterday when I was back there I didn't even see one. Timing is everything.

-Sara Nabizadeh

I arrived late to a party where a few photographer friends were heavily inebriated. They were awed by the fireflies, and insisted that, as the only sober one, I be the designated shooter. Lucky they were so insistent, because I was quite happy with the photo! (It turned out to be a pretty memorable party as well.)
Canon 7D, EF35mm f/2, ISO 1600, f/2.8, 30 Seconds.

-Zack Wussow

I had gone outside to get a shot of the sunset and remembered this contest. I only saw a couple fireflies blinking but didn't have must time to try getting any as it started to rain. As you can see, I got one good trail and the start of a second trail. I caught the firefly and shot the picture as it flew from my hand.

-Jeffrey Fetterman

Splat! Need I say more?!?!? Unfortunate firefly caught in the treads of my car on a late night.
Canon EOS T2i, EF-S18-55mm,1/5, f/5, ISO 3200.

-Kris Balow