[to3m]

This would probably be a good starting point. I've already found it quite useful sometimes to have programs output HTML+images so that the results can be viewed formatted. A terminal that could display that inline would be very handy! I don't really want one window for my text output and one for my HTML formatted output. There are some open questions (support links? do anything with javascript? etc.) but for my purposes just displaying reasonably-formatted graphical HTML output would be a useful improvement.

(Writing HTML files is workable, but a bit annoying to use in practice, because if you don't run the web browser from your program (= more windows) you have to tab over to the web browser and hit F5. And that assumes you're overwriting prior results on each new run, of course, which you might not want to do (= more coding and hassle).)

I suppose it wouldn't even have to be HTML necessarily, but HTML has the advantage of being some kind of standard and many people are familiar with it.