Re: WWYCD - The Night of the Dead
For Dr. Anomaly, it would probably settle a question that's plagued him for years. Both is parents are "missing, presumed dead" in the Bermuda Triangle. He's never been able to find any trace of them or their boat, despite years of trying. He honestly has no idea if they're alive or dead; if one of them visits him, that question would at least be settled. If that's the case, they'd likely spend the night talking, with Solomon (Dr. Anomaly) trying to both say all those things he somehow never got around to saying while they were still around, and telling and showing them what he's done and what he's become, and hoping for their approval.
If not his parents (either because they AREN'T dead, or whatever cosmic factors behind this don't see fit to send their spirits his way) I can't think off-hand of an immediate second choice, unless it's one of the great "gadgeteer" types from the past, like Nikola Tesla.