Default [Q] How much to "donate"

I have never had a problem paying for apps or software, 99c to $599 if I'm getting what I need. I have just started playing with my Sprint N3 got it rooted and trying roms which have all been "free"
So what is the "donate" amount? I have sent a few $5 to $10 out but really have no idea, I did search but found little. Some of the work the devs do is a little bit like magic to me and a couple of threads here have saved me a lot of pain.
I know the answer is whatever you like or think it's worth but I will go broke at that rate.
Thanks to all the people that contribute Andy

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