emacs + email/nntp
  wget
  vlc
  network-manager
  mutt
  empathy

That is just the highlights for libgnutls26.

I had forgotten about libcurl3-gnutls. There are a lot of things that depend on the libcurl3-gnutls, that list is long and distinguished. But I feel a little icky listing things without actually verifying they are affected. Just because they depend on the libs does not mean they use the bad code in the lib.

If you want to see what depends on libgnutls26 or libcurl3-gnutls in debian:

  $ apt-cache rdepends library-name

The --installed filter selects only those things that you have installed that depend on X:

  $ apt-cache --installed rdepends library-name

Scoreboard:

  dfc@ronin:~$ apt-cache  rdepends libgnutls26 libgnutls28 libcurl3-gnutls |wc
      629     632   10661
  dfc@ronin:~$ apt-cache  rdepends libssl1.0.0|wc
      751     752   11642