XEX is the executable file format used by the Xbox 360 operating system. It seems to be a crypto and packing container for PPC PE executable files, comparable to UPX  (http://upx.sourceforge.net/
) or TEEE Burneye. This would give more creedence to reports of .xex's being gigs large. Such speculation is also fueled by the presence of what appear to be clear text file and folder names. If games are Gigabyte sized .xex files then it's likely the 360 knows how to grab the section it needs into memory and decrypt/decompress on demand, instead of traditional all at once extraction.