I use the Banjo Bros bag Nom1ad mentioned and I love it. The side pocket fits a mini-ulock perfectly (now I use an Abus chain but it's still fine, easy access to the lock without taking your bag off). I no longer use the waterproof liner (since the plastic cracks at -40C, not a criticism, very little gear is designed for daily use where I live) but the "ballistic nylon" outer layer is water resistant for sure, and very durable.
Another plus about the waterproof inner is that it so thick it acts like a cooler, if you so desire, and fits 24 cans of beer.