First two examples

osd-clock

+#!/bin/sh
+date '+%d-%m-%Y  %H:%M:%S' | osdc -

osd-mpc-volume

+#!/bin/sh
+if [ -z "$1" -o -n "$2" ] ; then
+	echo >&2 "Usage: $0 [+|-]<percentage>"
+	exit 1
+fi
+mpc volume $1 | sed 's/.*volume: \([0-9]\+\)%.*/\1/;t;d' | osdc 'MPC Volume' '' --percent=-