I was just visiting a friend in Central California who told me about his church. Sounds like a nice church, in general, but what really struck me was that it has what you might call outreach-by-hobby.
The specific example he gave me was that the church sponsors a quilting group. By way of contrast, my church has support groups for people going through various kinds of trials: a cancer support group; a parents of ADD children group, etc. That's good, but this is a great addition. Not everybody is going through a trial for which they need support, but there are lots of people who have hobbies they'd like to share: quilting, bike riding, bridge, woodworking, model railroading, cooking, kite flying, scuba diving, painting, camping, and a thousand others.
When I heard about the church-sponsored quilting group, it occurred to me how much easier it would be to invite someone with a common interest to a group that shares that interest, rather than inviting them to church, which may be for many an alien and intimidating environment.
I think it would be great for churches to sponsor as many of these hobby groups as there are knowledgeable and competent church members to lead them, and for which the church can provide a solid core of members.
But how can these groups be a stepping stone to faith? Well, the church could let hobby groups meet in its facilities, thus making the church building a little more familiar and a little less intimidating to newcomers. Also, the hobby groups could start with a prayer. But most importantly, as the Christian members interact among themselves in a godly manner, and as they show kindness and develop friendships with the non-Christian members of the group, I think opportunities to share Christ or to invite people to church would naturally and comfortably arise.