The following software are known to use or support tcc builds.
Feel free to complete this list (*).

Name                   Short Description
----                   -----------------
bigz                   An infinite precision Z & Q library.
gawk                   GNU awk.
gmp                    Library for arbitrary precision arithmetic.
gnumake                GNU makefile.
mpfr                   Multiple-precision floating-point library.
mpc                    Complex floating-point library with exact rounding.
mpv                    A free, open source, and cross-platform media player.
openlisp               ISLISP ISO/IEC 13816 Lisp interpreter and compiler.
s-nail                 BSD Mail/POSIX mailx: send and receive Internet mail.
sqlite                 Embbedable SQL engine.
st                     Simple Terminal.
tcc                    Tiny CC which compiles itself.
zlib                   Lossless data-compression library.

(*) This list is ordered by name.