I'm absolutely sure there is life on other worlds, given that the universe is infinite, law of probabilities states statistically SOMEWHERE out there there has to be a world whose conditions favor a system of living organisms.
I don't believe we've ever made contact though, no.
The way I see it, there are two possibilities:
A, we eventually come across a planet with microscopic or extremely simple macroscopic life.
B, an intelligent species finds us.
When we do come across them, I doubt they'll be anything like any beings we've encountered on earth. Maybe they'll be remotely similar, but nothing like the menagerie of creatures we've seen in sci-fi movies/books/games/tv shows.
edit:
Ensiferum said:
Other - Do I believe there is life on other planets? Yes (They've already discovered bacteria on other worlds, haven't they?). However I do not believe we have enough hard evidence to support the existence of other "intelligent" life but I'll fully admit it's possible.
Nope, only signs of it on mars. No living beings yet.
mikespoff said:
The incredible improbability of life on Earth dwarfs the number of stars in the universe.
I'd assume that such a wildly unlikely event has not happened again.
Is the improbability of earth's environment computable? I'm pretty sure we've found at least one or two earth-like planets with our telescopes. We know mars once had water.
Because if it is computable, then no, it does not dwarf the number of planets in the universe, not by a long shot. That is, there is an infinite number of planets.