How can we practice Matthew 18:15 in a public forum?

Over at Judaism.SE, there's a question: How should we respond to objectionable content in a public forum? It got me thinking, how should we apply Jesus' teaching on reconciliation: > “If your brother sins against you, go and tell him his fault, between you and him alone. If he listens to you, you have gained your brother.”—Matthew 18:15 (ESV ) Sometimes, we are in a public forum with someone who is our brother or sister in Christ, and they say or do something that hurts us or is a sin against us. When in person or when a private communication channel is provided (e.g., Facebook, email, and many internet forums), it's easy enough to take them aside. But what should we do where there is no way to initiate a private conversation with a fellow Christian? Obviously, this very site is an example of where this might come up. But I'm not making it a meta-question since it's really a question about how Christians should behave in _any_ public forum. And of course, it must be an ecumenical position since, unless the forum happens to be specific to a particular branch of Christianity, the other person might come from any faith tradition (or none at all). How do we love those who sin against us in strictly public places?