ibuffer-saved-filters

ibuffer-saved-filters is a variable defined in `ibuf-ext.el'.
Its value is shown below.

Documentation:
An alist of filter qualifiers to switch between.

This variable should look like (("STRING" QUALIFIERS)
("STRING" QUALIFIERS) ...), where
QUALIFIERS is a list of the same form as
`ibuffer-filtering-qualifiers'.
See also the variables `ibuffer-filtering-qualifiers',
`ibuffer-filtering-alist', and the functions
`ibuffer-switch-to-saved-filters', `ibuffer-save-filters'.

You can customize this variable.

Value:

(("gnus"
  ((or
    (mode . message-mode)
    (mode . mail-mode)
    (mode . gnus-group-mode)
    (mode . gnus-summary-mode)
    (mode . gnus-article-mode))))
 ("programming"
  ((or
    (mode . emacs-lisp-mode)
    (mode . cperl-mode)
    (mode . c-mode)
    (mode . java-mode)
    (mode . idl-mode)
    (mode . lisp-mode)))))