Maximizing output from minimal input

gs2, 412 + 5.37 * 10⁹⁰² + 10^10903.1 bytes

1. f pushes 1\n2\nFizz\n4\nBuzz\n...\nFizzBuzz as a 412-byte string.

2. fô prints all of its permutations, so 412! * 412 characters.

3. fôô prints all permutations of that 412!-element list, where each element is 412 characters long, so 412 * (412!)! bytes.

EDIT: To put things into perspective, this is at least

10^{1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000}

bytes, dwarfing all of the other answers here so far.

Pyth, 26 + 1140850688 + (>4.37 × 10^20201781)

I have no idea if it is possible to calculate the exact length of the output for the third program. I can only give boundaries. It'll print something between 4.37 × 10^20201781 and 1.25 × 10^20201790 characters.

G
yG
yyG

This prints:

abcdefghijklmnopqrstuvwxyz
['', 'a', 'b', ..., 'abcdefghijklmnopqrstuvwxyz']
[[], [''], ['a'], ['b'], ['c'], ..., ['', 'a', 'b', ..., 'abcdefghijklmnopqrstuvwxyz']]

The first one prints the alphabet, the second one all subsets of the alphabet, and the third one the subsets of the subsets of the alphabet, which is a list of length 2^(2^26) ~= 1.09 × 10^20201781.

Obviously no computer ever will be able to compute this large list and output it.

CJam, 17 + 34 + 72987060245299200000 = 72987060245299200051 bytes of output

For easier comparison, this is approximately 7.3 * 10¹⁹.

P
PP
Ke!

Prints:

3.141592653589793
3.1415926535897933.141592653589793
012345678910111213141516171819012345678910111213141516171918012...

Well, the last one consists of all permutations of [0 1 2 ... 19] with the numbers squished together. I wouldn't recommend trying it out... (Try it as 4e! though to get a taste.)

Test it here: Program 1, Program 2, Sane version of program 3.