She demanded that she be acquitted.

Hi Lukas,

From a Brit perspective (although I don't necessarily expect too many differences):

This construction is certainly used fairly often. It's correct, I think, and thus would always be used in a formal context. But it isn't so formal as to sound weird or stilted in a casual context.

If you wanted a more casual (and shorter) form, you'd probably say something like "She demanded her acquittal", but that isn't a very nice construction.

Actually I suspect your example sentence is already a shortening of:
She demanded that she should be acquitted.

which fits better with wishes:
She wished that she could be acquitted
I wish that I could fly

I thought at first there must be loads of similar words, but I've struggled to find 'em...

Is this something to do with active and passive constructions ?
e.g.
I want to acquit him [ACTIVE]
I want him to be acquitted [PASSIVE]
I want to be acquitted [PASSIVE]

She demanded that the mistake be corrected = She demanded correction of the mistake
though that's also nouning the verb.

I'm getting rapidly lost in the intricacies.

Hope that helps a little bit, anyway!

Fisk