tab/csv spreadsheet-type tabbing mode?

[ivowel]

dear emacs experts:  I often have to look at files that come from
spreadsheets.  (No, I do not need emacs to become a spreadsheet; I did
look at these solutions.)

What I would love is a mode for a display that takes all the currently
visible on-screen data, and sets the tabs at the irregular places that
are warranted by the maximum length of each column on the screen (and
presumably sets truncate-lines).  oh, and tabs=field-delimiters could
be either real tabs, or commas (that are not inside quotations), as
they are in standard .csv files.

A second-best solution would be to set field widths not based on what
is currently visible, but based on the entire file's columns.

Having such a mode would make editing such data a lot simpler for me.
Does it exist somewhere?

pointers appreciated.

/iaw