Vrms (Virtual Richard M. Stallman) was originally a package for debian-based systems that analyzes the set of currently-installed packages and reports all of the packages from the non-free tree which are currently installed. It was ported to arch around ~2011 [0]. Presently it shows all beerware packages as a "non-free" license (LOL)
taco@ zen ~ % vrms
ip6tables-runitserv: ['beerware']
ca-certificates-cacert: ['custom:RDL']
connman-vpnd-runitserv: ['beerware']
wpa-supplicant-runitserv: ['beerware']
connmand-runitserv: ['beerware']
ttf-ms-fonts: ['custom:microsoft']
pacdep: ['GPL3+'] # LMFAO
dmraid-runitserv: ['beerware']
svopts-obarun: ['BEERWARE']
rpc.statd-runitserv: ['beerware']
dhcpcd-runitserv: ['beerware']
iptables-runitserv: ['beerware']
dbus-runitserv: ['beerware']
flashplugin: ['custom:non-free']
rpcbind-runitserv: ['beerware']
nfs-utils-runitserv: ['beerware']
runit-obarun: ['Creative Commons']
obarun-install: ['BEERWARE']
Non-free packages: 18
However, there are 160 ambiguously licensed packages that vrms cannot certify.
[0]
https://bbs.archlinux.org/viewtopic.php?id=76332