How do I make a really tiny font size?

I mean not size one, but smaller.

Or is it possible? On second thought, size one is actually quite small.

[sub]like this[/sub] This is 1 This is normal, and now I’m just typing so you can see how the line spacing is messed up because of the sub tags.
Well, I guess those are about the same, but using [sub] tags makes the font physically lower then the rest of the text (which, keep in mind)
throws off the spacing of the next line, as you can see.
ETA, we also have [sup]sup tags[/sup]

[sub]Many[/sub] [sup]thanks[/sup]!

I wonder what you would get by combining size 1 and [SUP]sup (or sub) tags[/SUP]?

ETA: Hmmm, doesn’t seem to make it any smaller.

Since Sup/Sub font is already size 1, what if we try to make it [sup]Bigger[/sup]. I guess that worked.

What if we go even [sub]Bigger[/sub] then that?

ETA Sup worked, Sub only works up to 4 or so then it it ends up being the same level as the rest of the font, or at least appears that way.

You might be interested in a discovery I made:

[sup][sup][sup][sup][sup]Thank you![/sup][/sup][/sup][/sup][/sup]