We had the idea to try to run a wireless ad-hoc network. So we did. In just a few minutes Daniel configured his Powerbook (or iBook? I don't know for sure) for ad-hoc networking, and I did the same on my Debian-based shiny new Toshiba Satellite A80-117.
I added the following lines to my
auto eth1 iface eth1 inet static address 192.168.0.19 netmask 255.255.255.0 wireless_mode ad-hoc wireless_essid foobar wireless_channel 11
Then I issued
/etc/init.d/networking restart and that was it. We could ping each other, ssh between our boxes, exchange files, chat, play networked games, whatever.
Although this is probably nothing new for most of you, it was the first time I tried it, and I was really amazed at how painlessly it was to configure and even more that it Just Worked(tm) out of the box. We were travelling a few meters under the earth, no cell phone connections possible, and still could do any networking stuff we liked. Call me easy to impress, but somehow that's just plain amazing.