There are zillions of possibilities:

1. -per Email: paul@hoplahup.net
   

2. -per phone +49 179 708 27 25 (stable mobile)
   or +33 6 68 29 03 45 (not very stable)

1. -per Skype (paul_libbrecht), or through diverse ways after you send me a link.
   

1. -or per Facebook or LinkedIn.
   

Signatures

I now regularly use PGP/MIME to sign my messages. Moreover, you can send me an encrypted mail using this standard and the keys below.

I employ, thus far, two private keys:

1. 1the key for paul@hoplahup.net with Fingerprint C6F8 EC89 52C5 8E21 71DD B05E 9423 87E4 A1CB 67B1 and this public key.
   
   

2. 2the key for polx@xwiki.com with Fingerprint 5D78 59D2 0E9A F86D 43A4  7600 FED5 7664 3970 EB45 and this public key.