As I live in a country not supported by Google Checkout, I have no option but to give away my apps for free on the Android marketplace.

According to the EULA (or whatever it's called) developers are allowed to ask for a donation, as long as it doesn't change any functionality in the application itself.

So my questions are:
1. If you have an app with "in-app donations", how much do you make on average per month?
2. If you have donated for apps or you're an "active donator", how much money will you spend on donations per month for good quality apps?
3. What is your stance on developers asking for donations in apps?

I don't want to include any advertising in apps, so this seems to be the only option for the time being to make some dough from my hard work...