I hope someone can help me here on a project I am working on. The overall goal is to be able to connect to about 10 linux computers via SSH through a single tmobile 4G hotspot. The computers would all be connected wirelessly. Right now, the hotspot is limited to 5 wireless connections.

I know the easiest way to do this would be get one of the 4G Cradle Point routers, but this project has already been budgeted without this expense. Is there a way to do the same thing as a cradle point with a linux box? I basically need the box to route it's 4G connection to the 10 machines.

Any ideas?

The simplest thing would be to get a USB 4g hotspot for one Linux system, and let IT act as the hotspot for the other systems. Easily done, and cheap...perhaps no cost, if you can exchange the Tmobile hotspot (providing you just purchased it for this project). Otherwise, you could just purchase a second wifi adapter for one of the systems, and let it act as a hotspot. A system with only one wifi NIC can't both act as a hotspot and use that connection for outgoing traffic. A second NIC solves that problem...one NIC is the AP, the other connects to the hotspot.

You don't really give any details (What kind of hardware, goals, types of machines like laptops/desktops, portability needs, etc.), so it's hard to give any real details. Chances are you can get this done easily for under $100.

Basically the hardware setup is:

The hub computer which is a old touchscreen tablet running Ubuntu Desktop 13.04 that is connected to the 4G hotspot. The intent is for this device to act as hotspot and relay connections WAN to LAN via SSH. All of the connections need to be wireless.

The machines I want to connect to are the same. They don't need to be constantly connected. I just need to connect to these individually every not and again to update content on them.

Ok...and you still don't say what brand/model of tablet, or what the capabilities of that tablet are. Also, you don't say whether or not the suggestion of the USB 4g dongle is doable, or the use of a second wifi NIC on that tablet, both of which will solve your problem.

And what do you mean by "relay connections WAN to LAN via SSH"??? Again, what is the goal? What are you trying to accomplish????
...and do they HAVE to be wireless?
Without knowing what the requirements are, it's again hard to say. If they only need to connect every now and then, just write a small script to try to bring up a wifi connection every now and then...if it gets one, perform whatever 'update' you want. If not, go to sleep for whatever time you like, and try again. So that at any one point, five of your 10 machines can get updates at once. Once the updates are done, bring down the wifi link, which will free up one of the five slots on the hotspot for the next machine to attach to.