If you get a USB type it will work at home or in a laptop. The one I had from Verizon worked under Winders as well as Ubuntu Linux.
Be very careful about the amount you download. The service plan I had was 5GB. There are service plans with even less (250MB if I recall correctly).
Also, be careful about roaming. Data roaming is super expensive. I live really close to Canada, and I had to make sure my card didn't try to connect to a tower up there. Fortunately, the software would warn me. I don't know if you're close to Mexico, or if the cell data services are even compatible, so this may not be a problem for you.