I've always loved the work the Fedora Marketing people do. See, for example, http://fedoraproject.org/wiki/Artwork/MarketingCollateral#Posters (They even have a cube!)
Maybe someone knows someone who's good at designing, that can come up with a simple design, with a small catchy phrase describing what MO is and which looks nice. I'll see what I can do.
]]>If there's a good reason to make a nice clean SVG version available, I can put it a bit of time to figure out how to do it.
]]>Have a look at http://mathoverflow.net/logo. There's a link to a high-resolution version of the logo. You're welcome to use it to make any kind of goodies you like. You can even sell MO goodies you make, so long as you don't generate much of a profit.
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