Excuse me while I dork out. (Synergy on Ubuntu and Windows)
I read today about the program Synergy, which lets you move a mouse (and copy and paste) across multiple systems as if they were one desktop. I've been wishing for something like this for a while, but figured it was impossible. I have the Linux monitor next to the Windows Machine, and have been using a KVM (minus the M) switch to switch my keyboard and mouse between them. With Synergy I can just move my mouse over. I can also copy and paste text and images.
In possibly my dorkiest move ever, I videotaped a demo (albeit a crappy quality one)
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Here I am copying an image from the windows machine and pasting it in Ubuntu. HOW FRIGGIN' COOL IS THAT?!?!
You can find better demos on Youtube (just look for "synergy" and "linux")