So how did you attach that fan to the case? Looks like an interesting idea seeing that its powered through the USB.

Can you selfhost a sync server? Be completely independent of them?

I think the big difference is that you can use it for free without any account needed, and all your data is stored locally in a format that remains accessible to alternative apps.

So the moment they start doing questionable stuff you are not a hostage to their app. There are alternatives, they are just not as nice as this currently.