I am looking to create a mini office network for our construction sites and looking to see what people recommend...
The project sites are all around the world, typically 4-10 people would need to access via wifi. We want it secured on the WiFi level (should be easy with WPA/WEP) and we want a NAS-type device which we can protect different directories (i.e. technicians can't see financials, other trades can get to a generic share directory only, etc)
I can mount items into a pelican case, but I would like to make sure that the individual items can withstand travel as they won't be in the same office more than a month.
I would think about what you really need to have on site. If you have a solid internet connection both at the worksite as well as back at your home office, you could access your stuff on your office's NAS remotely. You could secure the stuff via HTTPS and/or by setting up a VPN from your remote devices.
You can easily create different classes of users who have access to different directories on the NAS if you use a sophisticated enough box. I know that my Synology 1511+ has this capability.
The advantages of this approach are numerous. You don't need to worry about the file server's equipment (and the data) getting damaged at the site or in transit. You have easier central data management. You don't need to purchase a setup for each site other than your access point and internet connection.
You can't really create one setup for the networking stuff that will work worldwide as you're going to have different internet service providers, some of whom will provide and/or require particular equipment.
The new Synology software, DSM 4.0, also has a 'dropbox-like' functionality that will automatically synch local files onto the NAS. It's called CloudStation and while I haven't used it much since installing DSM4.0 on my box, it seems to run without crashing ;-)
The advantage of this is that the laptop's crucial files can get automatically uploaded to the server whenever the machine connects to the internet.
Disclosure: I am not a Synology employee, shareholder, or the like, just a very satisfied customer.