Sleep on absence of LAN activity, then WOMP

[sirquijote@lavabit.com]

Hi,

I performed a web search and could only find a post from 2008, and it had
no responses.

Debian 6.0.7 on a Dell Latitude D830 acting as a privoxy/SSH/NTP server. 
CLI only.

First: is it possible to sleep or suspend from the CLI?  No GUI installed
at all, nor is one wanted.  I'm not looking for data to be written to the
HDD, a la "hibernation".

Second: if so, can I alternatively tell it to sleep after an absence of
activity from my LAN, with WOMP/WOL? (Wake-on-Magic-Packet)

Thanks.