.I'm in the same "carry laptop, hate backpack" boat as you. One of these days I'm going to make myself a nice looking briefcase for my laptop and other teaching stuff, with some sort of hide-away rack mounting system. I haven't figured out how to do the mounting yet, and I walk to work this semester, so it's on the back burner. But one of these days . . .
Maybe one of these would suit your needs - Altura Urban Dryline 17 Inch Briefcase Pannier 42(L)x34(H)x13cm(W) Black. I use one for work - looks good enough to take to work on the days I drive and just clicks onto the racks on riding days.
Joel
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