Evilrabbit fantastic but you forgot Tory/Anders from Season 3 ;).
Even now that you've reminded me I still don't remember that.
So... wait, I thought a Cylon was like a robot. *doesn't watch show and is thus confused*
It is a robot, they're just highly sophisticated robots that have been evolving (for what we thought was 40 years but apparently now it's been over 2000 years) and look human, and they have blood and guts and everything, and they can interbreed with humans (they've done so at least twice, Helo/Athena and Tyrol/Cally), and sometimes they're sleeper agents programmed to think they are human, until they become activated.
Since it's after midnight, here's something for the Americans. The quote is from Will and Grace back in 2004 when he was just a senator, and Grace has a dream about him.