Philistine! It's not a matter of commercailly viable products or anything of the like. It's people having a hobby in making crazy portables from large consoles.
Myself, I'm in awe of the quality of these things. Despite looking like dubious industrial designs, the build quality looks like something you could buy in a shop. Do this guys work for companies that create prototypes or somesuch?
Also, do they take the innards of the consoles at full siz\e, or do they build their own mobos sometimes using modern smaller components?