Do you want the NSA (or Google, or your ISP) reading your email? Of course not! Do you want to simultaneously frustrate David Cameron? Hells, yes! Fortunately, you can encrypt your mail, using a tool that’s a wee faff to set up, but very easy once you get going! Mailvelope lets you encrypt or sign your email, even if you use a web interface. Those of you using hotmail or gmail, this is the encryption tool for you.
You’re going to have to click through to the howto page, as the route to the configuration menu is somewhat non-idiomatic for firefox. However, once you get going, encrypting is dead easy.
Once you get started, we’ll need to exchange public keys. What’s that, you ask? EFF answers all your questions about this. This kind of encryption is the kind that Edward Snowden swears by, so it really does work and EFF’s description is very readable.
UPDATE (7 Feb 2015): If you have trouble decrypting, make sure your version is up to date.
Ok, now that we’re clear on that, allow me to present to you my public key:
-----BEGIN PGP PUBLIC KEY BLOCK----- Version: Mailvelope 0.11.0 Comment: Email security by Mailvelope - https://www.mailvelope.com xsBNBFTTfUYBCADMpMs1fXzNP337GR+XoN26HssszqX8QwjrYaA+YVed5VaS yOyVUZ+4zJn+DGizOy8Ci1vH6CTw2qxX9QEgt0BtMVqwg4IDTSfbbndf0SEI fuyg0byu9G1DX8sgP1dlF2XQi7s30cmNLqR/a35a03mU1hkdmo+ZkllaNzGa uVeAMy6lt7jsOlE41mLzM8NQ6TSf2zh4/eY4v85vzlveh5fmTH0D+5SLhnU1 yzP3+V8wqEwO9zdEDXZMTSnB2zt5Io20QevKV433AJKzXze/i6t/tz3Z5VoE 7rg6nTCXOjjyg7vMGgcyaPKOTIYeWb3V56CiOL6nsP/OnxgeCVJOaXCHABEB AAHNJUNoYXJsZXMgSHV0Y2hpbnMgPGNlbGVzdGVoQGdtYWlsLmNvbT7CwHIE EAEIACYFAlTTfUoGCwkIBwMCCRBffO2vg3E8fwQVCAIKAxYCAQIbAwIeAQAA w4YIALthjNkvoOdNCZ3B89VBU5Xe9Xf6sRy/rU/JpxUQGt/eY6CC2sj0CVWf NeCoTMFuKbHJdX3RGOHVBgQYpdNcRSDpwjk7cv1jVOjM6l0Ace64R8JW5HZU diJji8ulHvyqpuFxUPRAG9jZfOyuHIdE58/6uxrdolcoW195d0p8E3pvcRzZ nDzpsEmAgOMFGnJGeVjjiOH2+egfx7xvKDFZmNc6dK5s/KPWo4rYLcay7/Jz 88gdMUKTUwVBKGo3rUpHqUwNriZMJVLeFC6MD+ZSFp8ApYlH+Dy9BsOQoVQL 5plJtuZqk+j+ODrHRZld8I54+2iGB/NIg8kUfMmwQuhsF3HOwE0EVNN9SgEI ALVDwZCzO85kWpkOnVxj7ZWvGRBcOEzfweHZhBQBNMR3do8KiKSIKAbwtSXR NxYXkwdiBcH3684ftnuxZSUoBU4i/YFySc9ruHE01DzL4kf1rTMRp+7xGG2t gxIBGbpz41Eg8kwj+5XZP2E6YPVDKjxrXgJ2Az/SwSGSSPaj17EgFFRHwuxL K7WnIix64J6C76eoUtJEjgPNq2b84haiGKLD2wG/BFwsJsziUWRJ/l0fWOcL WGnDbMM90gQJ9NvnTFMx7Pi+PP6nYJ5H+sUBwlQAs5pyzazyJKl/Yor7x29H VjU6R2qhQCaPz8SnYMzUOQK4XmRgmv/CbC6PbNyy+xkAEQEAAcLAXwQYAQgA EwUCVNN9SwkQX3ztr4NxPH8CGwwAABLtB/0Q23DqT5QlraCEGGg5AHbTy5ml bjTK0dI6JW/7kvngtMp8QEjAaLQDw2ii+6QEYzYDZrK0EiIimzKr/Wx//RFW G+3VQLySpvUdP48wfumR9uHgGFuyEKmswstEG61PhWL0j2+OOZJP9JOa5VS6 wfZZvJN0Za+t86xwlFP64KZwvy8rKG74yTD+jBdELIzm7LqjNoLa+2U1DNsN 4+o5NB4FrJAvQJT4Mrv/ff5mUQWDnGQys8ePdeZLOMvNXbvKWHLx4PEldYuf qHe6HDk3O822u+CO9+gOnw2e6cj5+gTBuP44ufgoua8JJQcbxAb0MDkagBqC VpdvIRjfYRjfKBFc =JaW9 -----END PGP PUBLIC KEY BLOCK-----