I think it was Selle An-Atomica.
The guy modelled a Brooks and modified it so it had a cut-out, and makes them in 3 different sizes (you'll still want to know your sit-bone width) and a gazillion different leathers.
I think TE sells it.
Yeah, here it is on TE
http://www.teamestrogen.com/brands.asp?brandID=121
He's even got the leather handlebar tape to match his saddles like Brooks! Cool!