Recommendations for a decent comfortable back pack for a reasonable commute, that may offer a little protection for a laptop. Leaning towards Deuter, but anything considered. Dont usually like carrying stuff on my back, but sometimes I need to…

Tick. Currently using a sleeve inside an old rucksack, but its not the comfiest.
Been looking at the Camelbak Daxio, which Leisure Lakes have for 20quid. Assuming you don’t need a bladder as well it looks ok – just not sure the space is there for shoes, shirt and trousers.

Pannier rack and bag.

You’re trying to carry a flat long object on a curved surface. You’ll always have a ‘fit’ issue and need to compromise. A courrier bag would let the laptop sit horizontally which would be more comfortable but won’t be as secure on your back as a rucksack. Again though you have protection issues – assuming you meant protecting the laptop.

not me but the bloke who sits in front of me in the office just sticks his laptop in a courier bag with the rest of his gear for a 15+ mile commute.

Mind you it’s a work laptop so he’s probably less concerned about looking after it than if it was his own.

I used an old DT spokes messenger bag with no padding for mine. Wrap the laptop up in a binbag to keep it dry and put a spare jersey between you and the laptop. That bag has died so I’ve bought one of these.

http://www.evanscycles.com/products/north-face/base-camp-messenger-bag-ec011920?query=messenger

Not sure if it’s going to be big enough for my laptop yet, an IBM T61 which is a bit of a monster. And a work laptop, I’d never carry a laptop of my own on a bike.

second the pannier and rack. makes total sense on a commuter bike*

* I’m assuming the bike is dedicated for that purpose