Drinking Soda as a CO2 Source in Aquarium

That's not true, the CO2 will gas off from the soda as long as the concentration of atmospheric CO2 is less than than of the dissolved CO2. A bottle of soda goes flat when left open whether you shake it or not. Shaking it will just gas off the CO2 faster.
 
How about stick one end of the tube into the tank, and the other in your mouth and just breath in with your nose and breath out using your mouth while you are resting or studying? :D (Don't do it the other way!)
 
AquariaCentral.com