There is WiFi at TE and maybe near the Meadows TP. Both cost the $9.95 to log in. Campsites and cabins use cable modems, also for $9.95 per 24-hr day. As I understand it, cabin modems are built in, but campsite modems have to be checked out at the check-in desk.
I recently bought a Verizon MiFi modem/router, so am independent of the Disney charges....but captive to the Verizon charges. I got my device for about $25 after discounts and coupons and pay $50 a month for 5GB of access. Never came close to using all of it, but the salesman said movie watchers or gamers might. I have had VERY good service at the Fort.
Although i have had a few dropouts at home, MiFi is more reliable than my NetGear router and ATT DSL line, especially at night. I am still evaluating whether to drop the DSL and use the MiFi exclusively. We are not movie watchers or gamers.