Neat product! I have a couple of questions, mainly surrounding the SPN.
* How does SPN differ from a VPN, in detail? In other comments you said that it's similar to Tor, but what does that actually mean?
* Does traffic get routed through multiple nodes before being routed to the destination? If not, what sets it apart from a VPN - apart from being able to choose different servers for every program on your PC?
* Is SPN intended to provide privacy against nation-state actors where simply masking your exit node is not sufficient, similar to what Tor claims to do?
* Who operates exit nodes (and any intermediary nodes in the SPN network), are they owned or rented dedicated servers, and does it include residential connections - to provide unblocking for streaming services?
* Is traffic routed through other Portmaster users' internet connections?