Something I've been working on lately is finding more little ways to connect with new people. Yehuda and Brendan are really good at this. Their m.o. seems to be find any little excuse to reach out and start a conversation, about even a narrow area of mutual interest. There are any number of conversation starters: congratulations on starting a new job, seeking advice on something of mutual interest, or a +1 on a nicely-articulated tweet.

Private chat or DM is a great medium for this, since you can just drop a quick question or message for someone and they can answer (or not) at their leisure. It's an all-around low-risk investment.

My hypothesis is that over time these little acts of outreach create lots of unforeseen opportunities to build allies and friendships. It's also a nice way to get to know people, since I usually find more formal social functions (conferences, meet-and-greets, etc.) more stressful and artificial.