http://www.headrun.ulg.ac.be/arclogo.png
http://www.headrun.ulg.ac.be/arclogo2.png
http://www.headrun.ulg.ac.be/arclogo3.png
http://www.headrun.ulg.ac.be/arclogo4.png
Feel free to build on the idea.
The intent is: a Roman arch resting on a Lambda, making a lowercase a.
The new official logo would be better if the blue was lighter in the small version.
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a lambda symbol under an church-style arch... lambda calculus, arc(h) & a nod to Alonzo Church
http://tinypic.com/view.php?pic=14n2y6h&s=5
worth another few minutes to refine further...?