Donations to ubuntu? Fiscal deduction?
Is there any online facility to donate to Ubuntu on a recurrent (monthly) basis?
Are there any fiscal/tax deductions for doing so? If so, in what countries?
You can pay for Ubuntu when you're downloading it:
There would be no tax deductions and there cannot be because Canonical Inc., the company that makes Ubuntu, is a for-profit entity; you cannot donate money to it and have a tax deduction.
Is there any online facility to donate to Ubuntu on a recurrent (monthly) basis?
No. The only way to donate on a regular base is to spend money in the Ubuntu shop; you could buy T-shirts and donate those or get tons of Ubuntu disks and give them away. Canonical believes this is the preferred method since both us and them benefit from it. Well technically you could pay for an an advantage deal and not use it. But that would be on a yearly base.
Are there any fiscal/tax deductions for doing so? If so, in what countries?
Not that I am aware; at least I myself have not seen any of that mentioned anyware as of today.