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.

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.