I entered the Digital Photo Of The Day contest at
Steve's Digicams.
Monthly winners get the cameras that were used for testing to write the reviews.
But when you're a daily winner, your email address is put out there without any attempt at tricking spambots.
Now I get spam every day, and I had managed to go for
years without getting any.
(It started the very day my photo was put up)
Many contests have drawbacks like this, so be careful and do some research first before entering any.
Read the fine print.
And DON'T fall for the one where you "win" and for only $XXX you can buy the book where your winning photo is published. They're a scam.