Current QuickPoll results for 185 entries:
What's the most annoying thing about aliens?
They're so smug about space travel, ...faster isn't always better.
Seti@home, ...what, you really thought you were looking for intelligent life in all that radio frequency gibberish?
Alien merchandise, (not counting the Geek Culture Alien glow in the dark t-shirt of course).
They run around naked, ...naked is fine, but the no genitals thing is kinda creepy.
Great computer graphics, ...inspired Nitrozac to do a 3-D comic next Monday.
Quit picking on us, ...their sense of humor isn't the greatest either!
(May not add up to exactly 100% due to rounding, and the constant intervention of Aliens.)