I needed a bike to do double duty as a winter race team training bike and a commuter. The 2012 Kona Jake The Snake, with a few modifications fills the bill perfectly.

The base bike is an all aluminum setup with 105/Ultegra mix.
I switched the CX chainrings to road-compact (Ultegra) gearing.
Different (carbon) seatpost and seat for comfort.
Different stem for fit.
I got rid of the junk cantilevers and replaced with TRP CX9's.
Of course, 700x28 Conti GP4Seasons give me the ride-with-impunity toughness and grip I need for Seattle winters.
SKS P35 Chromoplastic fenders with full reflective mudflaps
Lighting setup is a Planetbike Superflash Turbo and Niterider Minewt 600 Cordless.

I prefer a backpack since I have very little to carry (laptop and some small asundries - keep a large cache of clothes/supplies at work so no need to carry)