@cstross In terms of personal expenses, I could plausibly "consume" $300k for my own flat, and then maybe $30k per year for a comfortable lifestyle.
In terms of ambitions, I always wanted to run my own gamedev studio, so that would be something like $2-3M per year (I prefer to work with smaller games).
Funding stipends for my fellow leftwingers so they can do politics full-time could plausibly eat up about $10M per year, if I wanted to cover the whole country.
And that's about it, I think.