Don't know who would come up with the money for it,
We all should. Why not include a donation option in the client? Make it optional, but set it by default so that 0.01% or whatever of each transaction is donated to a fund used to pay Gavin, other developpers and for bug bounties. There was talk of a bitcoin foundation a while ago, not sure how thats going, but they could manage those funds.
I agree.
In fact, even making such a donation mandatory wouldnt be such a bad thing, like a tobin tax, or like the transaction fees we already pay to miners. Although of course some people will just fork and use a client without the "tobin tax", if you set a hardcoded lower limit low enough, most people wouldnt mind I think.
I don't agree. It'd be very bad from a marketing point of view to make such a mandatory "tax". I'm experiencing a lot of troubles marketing bitcoin to friends (key import/export is a big one, by the way, because I use casascius coins to get people started, they inevitably want to see proof that it's working (and it's a big "AHA", when it finally does). Fiddling with pywallet ("what? that's not even in ubuntu repository") and having the client "stuck on blockchain rescan" with no gui showing for minutes ("that pywallet screwed up bitcoin, now it doesn't start any more, glad I have a backup") doesn't help the cause. But that's a different matter).
Having a tobin tax would only add to the troubles I'm having "selling" bitcoin to people.