I thought I remembered seeing something here, so I tried to use the "search" function on a quick, non-logged-in visit. Can't do it. The board will only permit searches by logged-in members.
I'm not sure if this was an intentional decision or just the vBulletin default. If the latter, a suggestion: allow searches by anyone, logged in or not. I don't see a downside to this setting, and Quatloos frequently gains new members when folks find something on a google, look into it by further searching the board, and like what they see.
Peace out, guys.