Editorial Karim Bennaceur, Philippe Chomaz, Héloïse Goutte, Elias Khan, Frédéric Nowacki and Cédric Simenel Eur. Phys. J. Special Topics, 156 (2008) V-VI Published online: 17 April 2008 DOI: 10.1140/epjst/e2008-00605-3