so as you can see on the forums there is now a new donation widget, it was implemented yesterday and there are no known bugs. If you choose to donate, you can enter any amount. (It's best that there isn't a fixed donation amount, that's just derp.)
Feel free to donate, if you can't then don't worry about it. :>
Also, in case you're wondering where the money goes; It goes towards the website, and in the future it will go towards servers.