Hi, Janice ...
I think it was CruiseAholic who suggested pre-paid phone cards a while back. Great idea !!!
Too bad that Internet access locations on land aren't a chain-type deal so you could give a card for Internet messaging.
I once cruised with a gal pal on a no tipping ALLOWED ship ... we both made large batches of sinfully fudgy brownies for our cabin stewardess.
How about little bags of Jelly Bellies tied up with pretty ribbon? Either use plastic or your local liquor store will probably set you up with silver Mylar bags.
Take along a few holiday cards and write notes to crew?
There must be a ton more good ideas out there.