On Tuesday night we had a party at our house, to try and get our friends who are Christian mixing with our friends who aren't.
(A lot of them don't have any friends, or even co-workers, who aren't Christians.)
In some ways the party was really good and in other ways it was pretty disappointing. More than half the Christians who came along didn't mix with anyone they didn't know (so they only talked to other Christians) and left the party quite early. However, the Christians who were sociable got to know our other friends, and we all had some great conversations.
By about midnight, we ended up sitting in the lounge, mostly singing and passing Alt Tab's guitar around (those who could play). We ended the night by watching the video of Alt Tab and Kate's baptism - someone who hadn't been able to make it to the actual celebration wanted to see it. It was after 4am by the time I got to bed.
I'm thinking that in terms of getting the Christians who didn't mix to mix, we might need to take them individually to other people's parties, so that they won't know many people, and will have to interact with unfamiliar people.