Ah, I don't mind flat out asking someone directly. I've found that every one I've asked, so far, has remembered me. I'm sure I will come across someone who has no idea who I am and believes me to be a creeper, though. "Why does this PiroMunkie n00b keep on viewing my profile? What kind of name is that anyway?"
I had to do that when I came back. Heh, it really was fun lurking around asking people if they were who you thought they were. But I don't think I directly asked them... If I'm not mistaken, I asked the ones that I could identify to confirm the others' identity for me.