Back in 2004 I owned a a standard black Xbox, and had an opportunity to buy a Japanese Import Halo 2 Special Edition with a unique Translucent Green case. I then modded it with a top of the range Xecutor 3 mod chip, put a UK PSU in it, bought an LCD front panel for it, and generally spent far too much money on it. About £350-£400 in all I think.
Then in 2011, I spent yet more on it by swapping out the HDD for a near-silent 2.5" laptop one, installed a silent fan, bought the HD cable, and installed XBMC4Xbox on it and configured it up. The idea being it would be quiet enough to use as a media centre.
Then once it was all working never used it again.