Onion access

Open-source Bitcoin blockchain and mempool explorer you can self-host or reach over Tor. No account, and self-hosting avoids leaking which addresses you look up.

Donation-funded platform offering email, cloud storage and collaboration tools with no personal information required at signup. Runs on free software.

Long-running free email provider that asks for no personal information at signup and is reachable over Tor. Aimed at users who want a throwaway, identity-free inbox.