Protonmail is great, I've been using it for a while now and can not say anything bad about it. Can't wait for them to finally release their calendar service soon!

It is interesting that they aren't selling their BTC. They must have enough income from other payments to pay their expenses. Maybe they just don't get that much BTC payments? It is a rather risky business move though. Oh well, it seems to have paid off 

I'm curious if they are planning on accepting other cryptos in the future..