You can keep everything you ever write

The whole work of Shakespeare is about MB. For an impossible upper bound of hand-typing:

100	words per minute
5	characters per word
60	minuter per hour
24	hours per day
365	days per year
50	years
16	bits per character (utf-8)
210240000000	bits
210.24	GB

Maybe more realistic:

15	words per minute
5	characters per word
60	minuter per hour
4	hours per day
250	days per year
20	years
16	bits per character (utf-8)
96000000	bits
96	MB

With compression or structural sharing, I’d be lucky to get 10MB of ideas down in my lifetime.