I think being called Aisaka in person would be strange, but most of my friends off this site just call me by my username there even though they already know my actual name. I've been considering asking if they'd call me by my name since I tend to call a few of them by theirs, but it'd be weird to ask for a "first name basis" thing with people I've known for years like that. I'd answer to Aisaka if you called me it in person, I'd probably just think you're weird if you already know my name. Introducing myself as Aisaka would be awkward as well.
As for something weird, a friend of mine once tried to corrupt an old username to "Eggplant" and call me that in person. That was a very weird day.