Here are some links to friends. Some of them happen to do Machine Learning as well, so they are in the scientific section.

Scientific

Nikos Vlassis

Tim van Kasteren

Gwenn Englebienne

Ben Kröse

Bas Terwijn

Konstantinos Chalkias

Ioannis Refanidis

Louis-Philippe Morency

Sarah Favre

Max Goebel

Ioannis Karamouzas

Friends

Vasso Noula

Dimitris Andreou

Miscellaneous