TIL: #bash provides pseudo devices for TCP and UDP connections:

echo "hello" > /dev/udp/127.0.0.1/1337

or

exec 5<>/dev/tcp/www.google.com/80
echo -e "GET / HTTP/1.0\n" >&5
cat <&5

I'm baffled how I've never discovered that until today.

@fribbledom Ick. gawk too, IIRC. Should bu system level, so everything has access (like Plan 9, as noted elsewhere).