I keep work, hobby and private strictly separated and thus communications which try to come through the wrong channel are silently rejected. Thus please use the proper channels.
My preferred way of contact is per email at: Jeroen Massar <email@example.com>.
While I am present on various social networks, email is a much better way to contact me as I do not regularly check social networks.
One can also use the vCard containing my contact details or scan the QR Code on the right.
Like most other people I don't like spam, as such that address is filtered by the excellent SpamAssassin. The policy is set to reject all viruses and spam during SMTP-DATA thus I won't see them but the sender will receive a NDR indicating that it was rejected and the reason why. PGP signing and encrypting your email ensures that the message passes. Don't forget to publish your PGP key in the PGP Keyservers if you want answer though.
Pretty Good Privacy
My PGP keyID is 123421B735578C46 but due to collisions better check the full fingerprint below or use the QR Code to import it to your device. My old keyID was 333E7C23, still active but should not be used anymore.
123421B735578C46 (4096 bit, 2015, active use): 6AC3 85A3 E350 0A2E 07AE 5548 1234 21B7 3557 8C46
333E7C23 (1024 bit, 2003, deprecated): 48E8 2BD4 3B4A 622E 405C 3A35 29AA 2852 333E 7C23
As secure communications platform I have chose Threema. From independent audits, it looks like they are doing the right thing, and as they are in Switzerland, I can easily pay them a visit. One can ask for my Threema-ID using a PGP crypted message if wanted.