Well, there's the Mears Shuttle for about $14 per person round trip. You need to call at least one day in advance to arrange a pickup; you pay the driver on the way to the other parks; and they give you a number to call two hours in advance to arrange your return. You may travel in a van, or you may travel by bus - it depends on, I think, demand and what Mears chooses to send.
Or you could take the bus from Pop to Magic Kingdom or Epcot, then take the monorail to the TTC, then out there in the bus area of the parking lot somewhere you can catch the city bus - Lynx - for about $1.25 per person each way. I'm reasonably certain you can get a bus directly to SeaWorld, but I think for Universal you need to transfer.
Or you could take a taxi - about $40 each way for Universal, less for SeaWorld, for up to four passengers.
(all prices subject to change)
we will be going in december.
