Yes, there is something there, isn't there? The bottom of the element is raised off the baseline, same with the b and d, and the corresponding element on the p and q are set below x height. I didn't know if it could really work, but then someone posted about Serif Gothic and I noticed that it did it as well.
I wouldn't call it BASEsans http://www.emigre.com/EF.php?fid=79
Is this*
http://behance.vo.llnwd.net/profiles18/1228291/projects/4160315/1403dc9d...
where you got the idea of the funny tail on the "a"?
* http://typophile.com/node/97318
hhp
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