|Yes, it can be done. In no way should you buy a $400 device from Verizon.|
Here's what to do. I'll give you high-level, step-by-step instructions. If you need help with a particular step, please ask.
1. Get a wireless access point with at least one wired ethernet port. It doesn't have to be a router. in fact, the setup will be easier if you use a device that's not a router. Your laptop with the aircard is going to handle routing, so you don't need a separate device for that.
2. If you end up with a wireless router anyway, disable DHCP on it. You are only using the switch feature of this device, not the routing.
3. Enable Internet connection sharing on the laptop with the aircard
4. Connect the laptop with the aircard to the wireless access point. It can be connected via wired or wireless. Makes no difference.
5. Connect your wife's laptop to the wireless access point. It can be connected via wired or wireless.
6. Turn on file sharing on your computer and your wife's computer.
7. Connect the PS3 to the wireless access point. This will probably be done via wired connection (anyone who knows PS3 feel free to contradict me here).
That's pretty much it! Step 3 is only necessary if you want to share the aircard's internet connection with the other computers. The other steps, whether you perform #3 or not, will give you the ability to share files and stream media between the two computers and the PS3.
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