Dear Laurent,
>
> Here is a question about accessibility of ASCII characters
> in **Russian** keyboards -- MS Windows for a start.
> But DOS and unix too.

I work with all of them, and the keyboard is just the same... :)
but the troubles exist:
1) we have different encodings (alternative (cp866), windows (cp1251), unix
(koi8r), others),
2) we have different layouts (correspondence between characters and their
places on the keyboard): usually Cyrillc chars are on the same keys as
Latin, but are colored red instead of black, the layout corresponds in
general to that of typewriter; some chars (~`\|/|?'",.;:@%) exist, but are
placed on different keys in Cyrillic and Latin modes (that also varies with
type of keyboard and Cyrillization program and specific layout scheme (that
may be reprogrammable)).

> While typing English, which of the following ASCII non-letter
> characters are available on your keyboard in a simple
> keystroke position, and which with modifier key(s) and which
> only with extreme difficulty.
>
>    ! " # % & ' * / ()
>    < = > @
>    [ \ ] ^ _ `
>    { | } ~

On my keyboard
    .\=-                         are typed directly,
    !"?;%:?*()_+/,         are typed using Shift,
    others require switching to Latin mode
    (1-2 additional keypresses, depending on the scheme used).

\bye
Mikhail Kolodin, mailto:myke@mail.ru, http://myke.da.ru, ICQ#10895085,
2:5030/207.16@FidoNet