Do I believe in the prospect of other complex and intelligent beings in the Universe? Absolutely. I think the Drake Equation was a little optimistic, but now that we know radio waves actually dissipate completely by 1 light year out, the fact that we haven't picked up signals from another planet is no indicator that there might not be another civilization close to us (it also means SETI is a total waste of time, but....)
Now, do I believe there are flying saucers coming to Earth to abduct people and harass our planet's rednecks and cattle? No. i don't want to call people liars, but... come on. Then again, I am sure many of them are convinced this is happening to them, in which case they need help.