After a day of hacking, bashing and drilling I've slimmed down the GROK2 robot, reducing its width by 40mm on either side. This robot has an AL-101 chassis (Zagros robotics) and fortunately it's made from 3mm aluminium, which is just about sawable with some exertion.
This should give the robot more clearance when passing through doorways. It's still wide enough for a netbook, mini-itx or even a full sized motherboard but it's no longer wide enough to carry the laptop - at least not in the usual orientation.
It's always been in the plan to eventually have some permanent onboard PC, and at present it looks as if netbooks are just not quite up to the job unless they're the latest and most powerful devices (which are expensive). So I might have a go at installing a mini-itx, which are much cheaper than a high end netbook. I could then use a laptop or netbook to ssh into the robot. I have a couple of spare SATA hard drives which could be used, and also a couple of USB wireless adaptors. Another advantage of the mini-itx boards is that they can be run off of a 12 volt supply, which avoids the wasteful DC->AC->DC conversion.
All in all the future for robotics is looking very good, particularly for low hanging fruit applications, such as fetch and carry or just hawling stuff around. I think it would be quite feasible to build a prototype shop/supermarket shelf stacker robot, and also to add an autopilot feature to mobility scooters or wheelchairs.