I say, the closer to the truth, the easier. I agree with the suggestion of "meeting up with some online friends." The only way this would be a problem is if you're talking to someone who loves chat rooms and might like to know what this cyber community of yours is. However, most people won't. I definitely advise against making up fictitious conventions, and if you tell them you're going to baseball games, they may well want to hear how this or that play looked from where you were sitting. If you say you're meeting up with some online friends, you're not lying--you're just leaving out the fact that we practice our arpeggios on each other's ribs.