For those not seeing tonight's UFC fights, which looks awesome, the Mayweather-Marquez matchup is interesting. An HBO special highlighted Marquez's unique training ritual; watch and enjoy.
Interesting to see he prefers it fresh (one would think it best like white wine, at 40 degrees Fahrenheit). Now, if you are on a life raft and dehydrated, you should drink your urine a couple times, after which the concentration of minerals and salts outweight the hydrating effect. If you drink your own urine (and know where you've been), the chances of bacterial infection are pretty slight, and it is sterile (unlike poop, which has thriving bacteria from the large intestine). Indeed, urophagia is a somewhat popular homeopathic remedy.
But, 'can' does not imply 'ought'. There are a lot of energy drinks out there that replace essential nutrients and taste great.
BTW, anyone who says there is no greater fighter than Mayweather, in terms of artistic talent and athleticism, has not seen Anderson Silva fight.