Wirelessly posted (iPhone 3G: Mozilla/5.0 (iPhone; U; CPU iPhone OS 4_1 like Mac OS X; en-us) AppleWebKit/532.9 (KHTML, like Gecko) Version/4.0.5 Mobile/8B117 Safari/6531.22.7)
Possibly not big enough but Knomo looks classy and I'm a big fan
http://www.knomobags.com/uk/men/bags/briefcases/warwick.html/
For large lifting I use a Booq Cobra L
http://www.booqbags.com/All-Products/Cobra-laptop-bags/Cobra-case-L
I find Tumi a bit too common and boring, stereotypical 'banker on tour'.