I don’t think there’s a supervillain whose civilian name is unknown and would be useful to the heroes and government, and is known to the readers.
The Joker, for instance, has been in and out of Arkham and the Slab, and probably Blackgate, without anyone (possibly even him) knowing his real name. His name (might) be known to the readers, but it would do nobody any good to know it. It wouldn’t help the cops and Bat to catch him, and any doctor who tried to use it to help him would find themselves getting a face full of Joker Venom.
You might get something by selling it to the press…but again…Joker Venom…this time, though, the people at the newspaper who buy it, and you if you give them information that would let him find you.
The only ones I’d go to for help would be Superman or Batman. The rest of them would just have Zatanna magically lobotomize me so I’d forget their secret identities. I’d hate to become a joke villain for the Teen Titans.
Clark Kent seems like a better bet; shouldn’t be too hard to at least get to the Daily Planet’s front desk, and if you leave a message like “Alan Scott and Wally West said to get in touch if there was any trouble”, you’d get his attention pretty quick.
So have any comics dealt with how many freaking crazies there must be sending their conspiracy theories/paranoid delusions to STAR Labs, Reed Richards c/o The Baxter Building, etc? And how these organizations sort out the loonies from the honest-to-god time-lost travelers/demonic possession cases/people with evil twins/etc?
This is why I chose Oracle instead of Clark Kent. The ability to find her is enough to get her attention as a serious player. However, if you know who she is, it’s easy enough. For one thing, I’ve got some of her her online aliases: Rollingthunder, for one. And for a second, her dad’s listed, and if I call him, tell him it’s about her… after-work activities, I should get her attention. Maybe not her address, but some connection. As long as I’m perfectly honest and careful what I say, I probably won’t have to deal with more than one or two shots from the Black Canary. For that matter, her phone number (As Babs) is probably listed.
If it isn’t, a few postings in select areas with statistically significant information will have her finding me. Which will also work. I’d use the Gotham Craigslist.
For Marvel… I’d do it the easy way. I’d go find a certain house on Bleecker Street, provided Status Quo is active. Currently, I’m not sure of the status of the house, so if it’s not there, or I can’t find it, I’d just walk in to the Baxter Building and talk to Roberta. The fact that I know how Doom scarred his face, and who he was trying to reach should get Reed’s attention. If not, the fact that I know who Valeria’s godfather is might. If not, the fact that I can describe what God looked like to them probably would. They’ve met him. Bears a strong resemblance to Ben, and carries a #2 pencil.
I wasn’t being sarcastic. Pre-Crisis, at least, Superman’s dual identity did nothing at all to protect his loved ones. His parents were dead; Clark’s friends were all Superman’s friends; his only living relative was as demigodly as he was; and his friends as Superman were all generally super-heroes.
Post-Crisis, of course, Ma and Pa Kent are back. Well, just Ma, now.
I guess I’m just the evil prick of the group. I don’t sell anything. I just walk up to the Daily Planet, find Lois’ biggest competitor (If she’s still there that is. I haven’t read the books in decades.) and tell all I know. I out everyone I can, hero and villain alike and watch the mayhem.
Oh, I should have been specific: I’d ask Batman for help, not try to out him or anything. And maybe ask for a job. I’m sure they have something I can do.
Martian Manhunter: We’ve received a disturbing communication. A man in Metropolis claims to know the secret identities, origins, powers, and weaknesses of every hero on Earth.
Flash: That’s impossible! He’s probably just some crank.
Batman: Still, we should send someone to investigate, just to be prepared.
Superman: Let’s send one hero to check it out. If the guy can accurately describe his background, then he may be onto something.
Oh god not Hawkman. I could do it. Sort of. Maybe.
Twit: The problem with doing that is that you’d wind up very dead very fast. If not from an anti-hero, then from a villian who wanted to probe your brain for forgotten details. Or from a ticked off Joker that’s annoyed you spoiled his fun. Or a really raging Lex who can’t believe he was fooled for that long by that fool. Seriously. Splut. Dead.
Or maybe, you’d get lucky and just get mind-raped by Hector Hammond who wants to know everything you do about Green Lantern. Trust me, it’s skeevier than it sounds… if you know what he revealed to Hal a year back or so.
Of course, most people would only be dangerous to two of the Big Three: Bats and Supes. Wondy… tends not to have a secret ID, since Crisis.
Someone like me, though, could be dangerous to everyone up to and including the Guardians of Oa. Heck, some of what I know could really, really disturb Darkseid. That’d be bad.