[slitaz]

The problem is that you cannot force a "subscription" with open-source software. It would not and should not be called subscription.

You could ask for a regular/monthly contribution. There is something similar with Ubuntu and others; when you download Ubuntu, you are asked to make a voluntary monetary contribution.

[majidazimi]

Whatever the name is, it is definitely possible to build a distribution around subscription model just like commercial distributions as RHEL. It only needs to reduce the price so much that no one cares about the fee. The company needs a predictable and sustainable income - business model - to plan for future. I call donation model a hopeful business model.