Has anyone come out with a Member Number hack which could appear under the Member name and title in the postbit template? I ran a search and didn't find anything and realized it would be harder to do than I had originally anticipated. Any ideas?

$userinfo[userid] -- that's all the member number really is. Getting "this member was the Xth person to register" type thing would require additional queries, or at least a change to the join.

Just put:
somewhere in your postbit template.

<edit>
I see I was beaten by Ed :D
Surely $userinfo[userid] would give the ID of the currently logged on user rather than that of the poster?
<edit>

Ahhh...perfect. Thanks guys. I was in the process of going through all my templates looking for that parameter.

LOL....I'm member number #5 of my own Forums and yet, I'm the first person to join them which I verified in the Member List. I wonder who the first 4 members are. :)

No, that's $bbuserinfo[userid] .

Interesting...I remember when I used UBB, I, too, was member #5, although I was of course the first person to register. Did you import from UBB?

Yep.