Well I'll certainly be able to bring my 360 + extra wireless controller, component cable, games.
Other stuff I can do aswell is 15" monitor + 19" monitor, and maybe a couple of extension cables depending on what you need.
(that's almost everything in my room bar my base unit and speakerslol)
I'm leaving a lot behind but I'm bringing:
360 + 2 pads + VGA
Wii + 2 pads + component
20" NEC 20WGX monitor
5 patch cables
3 4-way extension sockets (and maybe 2 10-way if I can be bothered unplugging my stuff
1 bottle skittles vodka

If anyone can bring a portable stereo with a line in on it I'd love you long time!
Edit:
Just a thought... you got aircon in this room?
