Gosh, thanks to everyone for the responses.
kelly, you got the specs right. One thing, I don't even know if my Tandy has an internal modem. I bought a floppy disc drive for it (when I gave up on the cassette recorder) but that was all. I know you are right about it not being worth the trouble, but it is just such a neat little machine, and I guess there is a nostalgia attached to it.
krissy & Mayo, those are great links. I'm going to see what they have to say.
Steve, Klaus1, email would be no problem -- as kelly pointed out, I have a total of 32 kb ram on it (I did the upgrade from the 8kb that came with it!) so I could email pretty much anything if I got the right connection.
I think I also bought something like a null-modem cable? Does that sound right? I was going to use that to transfer documents to my next computer, the Performa 6205. I recall trying to do that, but couldn't get it to work.
Gregg... Gregg. Leave the poetry to Dick, okay?