Steam

None.

The surreptitious opening of intercepted postal correspondence.

"Electrical use".

"Electrical use".

... as if Doorman reads all of the original post before responding.

Cleaning motors (with the proper precautions and attention to details).

Steam can be used to initiate an electrical signal from a steam sensor....

.

The question is difficult to answer because the your restriction essentially cuts out most other uses with the exception being the one example you provided.

'Steam' (water vapor) can be pumped into a room to reduce static electricity.

As a conducter to ease initiating an arc???

(yummy! Plasma fried hot dogs!!)

That's actually a somewhat arcane reference, since the steam is not actually used to create electricity in any sense any more than water or wind are. Steam turns the turbine the same as the two others. The turbine turns the generator. (These are generalities.)

You could just as easily ask "apart from power generation, what are the other electrical uses of wind?" or "apart from power generation, what are the other electrical uses of water?".

_{^{sic corrected}}