If Meta requires OpenID, then FIX YOUR STUFF!
1) Attempting to ask or answer a question here without being logged in produces the following error message:
"•name and email, or your OpenID, are missing"
That implies that a name and email address would be sufficient.
2) Click around enough (the "register" and "log in" links are confusing and the whole thing needs re-thinking, so I can't remember for certain, but I think it was on the "forgot your account information" page, which I can't find again at this moment), and you'll be informed, and I quote (yes, I copied the text when I had that page open in my browser):
"...does not require an email address to participate..."
I guess that's an ambiguous exerpt, but the text on that page led me to believe I didn't need an OpenID associated with an email address.
I'm a geek too, but I prefer NOT to use OpenID, and the hassle of using SO without one is so great, that I try to avoid SO for the most part, which is a bummer, because everything else you've done is AWESOME