Your body needs the energy to properly digest food. So to get the most out of the nutrients you consume and your workout, eat before exercising or 30 mins after fruit, two hours after veggies, three hours after grains four hours after meats and poultry.
So it's not a matter of value, it's a matter of what you need it to hold. And a matter of affordability. The movies will be the biggest space hog. So if you only put the movie you want to watch next on the iPod touch, so one (or two) movies at any given time, you will have more than enough space with either 16 or 32 GB. People watch movies once (twice if it's really good); they do not watch a movie over and over again like listening to songs.
You must use this number, not 5,000,000 when calculating memory needed by the hash array. Thus, in our example, the memory needed for each hash array is: 8,388,608 * 8 = 2^23 * 8 = 2^23 * 2^3 = 2^26 = 67,108,864 or approximately 64 MB. Since we have three hash indexes, the memory needed for the hash indexes is 3 * 64MB = 192MB.