Those awesome BeOS demos! They would open a dozen apps to max out both CPUs (25 or 33 MHz as I recall) and then show that you could grab any window and drag it

Those awesome BeOS demos! They would open a dozen apps to max out both CPUs (25 or 33 MHz as I recall) and then show that you could grab any window and drag it around, and everything else would slow to a crawl, but that window, the one you were interacting with, was still snappy. Then they would shut off one of the CPUs. Everything was as slow as winter molasses. And they would grab a window, and it was still super snappy, while everything else almost froze solid. I miss being the center of my computer's universe like that.