"Case-Mod" contests would always hand the winner award to cases like SOME of those pictured.
These people are artists, which means that the experienced person might take months with the work.
For myself, I have a massive case-mod-makeover (massive in two uses of the adjective) in progress.
I've been through terrible frustrations, once I was misled into thinking that a faux "chrome" paint finish would be inexpensive, and just require moderate care to do it right. I would've paid for the chrome-plating. Do not consult a former motorcycle-shop owner for whom paying for software and up-to-date hardware -- is like pulling teeth. They give mixed-up advice. Like I said -- I should've had it chrome-plated.
I've finally received offer from the paint-manufacturer -- supposedly because I had been in touch with their tech people and sent them an e-mail expressing disappointment in one of their clear-coat formulas. Because of the cost to me, they've offered to re-do the case for free.
I don't know if I have the time or patience for the kinds of artistic expression shown in the link.