Well, as you increase your terminal's rows/columns, each character starts to approximate a pixel. The included screenshot is around 50 rows (double the "normal" ~80x24). Emoji and Unicode can probably stretch this further.

I'd love to see more quality terminal apps come out. I feel like the software (excepting, of course, the browser) I use is perfectly bifurcated into "terminal" and "webapp" domains. I just don't see to have much use for traditional GUIs anymore and even prefer locally hosted webapps to them.