nMap for Local Network

Easy Way to Find ODROID/RPi/Arduino On Your Network:
sudo nmap -sP -PS22,3389 192.168.0.1/24

 

Returns:
Nmap scan report for 192.168.0.xx
Host is up (0.00025s latency).
MAC Address: XX:XX:XX:XX:XX:XX (ODROID)

Quick nmap tutorial:
http://www.cyberciti.biz/networking/nmap-command-examples-tutorials/