Cat as a model category

Here's a question I've already asked on the algebraic topology mailing list. I received several very interesting replies, but there seems to be little published and I'm curious what else is out there: I have Thomason's 1980 paper "Cat as a closed model category." Are there any other references for model category structures on Cat, the category of small categories? --Steve Costenoble matsrc@hofstra.edu Dept. of Mathematics Hofstra University Hempstead, NY 11549