I have some nice projects that I already tried to implement with other expensive Linux embedded hardware, some of the prototypes failed due to HW/SW limitations, some did succeed, but was to expensive to implement as a 'viable' solution. I will start with a simple suggestion, once I have some Raspberry Pi in my hands, I'm sure that I will have another interesting topics to open
There are situations that I need to remote access my home/office/wife/friend PC, but I'm unable to do because the PC is turned OFF and the office is closed during the weekend ... I've been developing the idea to have a cheap and energy efficient Linux embedded board inside the PC that will have internet access via Ethernet connection, and by using XMPP protocol (been testing with Googletalk chat service), be able to send remote commands such as WAKE_UP, SLEEP, SHUTDOWN, etc, GPIO pin will then activate (maybe via relay switch) the PC power button ... I can tell you guys that I already had such solution, but my previous Linux embedded hardware platform didn't have support for a standard Linux Distro, making such XMPP app would require extra efforts (porting stuff to OpenWrt is a bit complicated and weird - at least for me)!
I've tried some C code libraries, but had hard time with the library dependencies and gave up! I decided to test some web-tech tools and found a nice way of doing this via Ruby, or even node.js (this last one still on tests).
I came up with this simples ruby script, that allows me to request a remote command over Gtalk chat (using XMPP protocol):
(this is still an initial proof-of-concept script, but is currently working, just a matter of calling a GPIO service/script/app)
Well, I had the same problem trying to get Ruby running on my previous Linux embedded hardware, but I'm really confident that I will have success running this over Raspberry Pi board.
This solution could also be used for the Raspi to remote control some Relays connected to the GPIO port (via transistor circuit), and by connecting this relays to some power-plugs could also control other devices (OK, this is kind of dangerous, proper caution would be required on this - but have some other ideas for this one - RF plugs)
Pretty straight forward, as long as I have some Standard Linux distro such as Debian on Raspberry PI. Really hope to post an how to on this