I see a lot of people posting, but very few people actually trying to address your problem.
The fact is when you're at sea you'll be away from any kind of reasonably priced internet service. It's just a fact. No land lines on the open ocean, and bi-directional sat service is expensive.
Cruising sailors / powerboaters are usually stuck with either paying insane amounts for some kind of real time bi-directional satlink (which is what the ship has) or spending a lot less for some sort of Store and Forward satellite system.
Another option open to cruisers is using HF radio and RTTY to send email around. Slow, but surprisingly reliable. That'd require either a marine HF, or a Ham Radio license, and the appropriate hardware.
None of those may be an option for you.
There is a product called Sailmail that might suit your needs. Essentially a little hand held device that has an accoustic coupler in it. Call into the server to send and receive your mail over any phone.
Ultimately, I'll give you one piece of advice. Namely: For waht you need, forget Slashdot. You'll get more people talking about how many seconds a day 100 minutes works out to. Try something like the user forums over on Cruising World or any of the other cruising / sailing forums.
Talk to people who actually know the subject matter at hand.
and enjoy the semester.