Sometimes programmers need answers fast. I believe that high-reputation users should have the possibility to get a question featured within a few hours instead of the current two days (thanks @agf). There should, though, be an additional cost for doing this. My suggestion is that it should cost triple the amount of reputation. This means that one would need to spend 300 reputation to set 100 reputation bounty on a question.
I am declining this for a few reasons:
There is no point having a bounty on a question that is already perfectly adequately answered, in most cases questions are answered just fine without bounties.
It leaves a a bad taste, "if you want your question really answered you better fork out 500 rep when asking it".
It introduces some loopholes by making it more complicated to close and move off topic questions to other sites. (mods need to refund and do the move themselves giving them more work)