Though I'm usually in favour of the separation of Church and State, if it comes at the cost of losing many of the religious public holidays we have recently enjoyed here I'm not so sure :). In reverse order, we have recently had days off for Fronleichnam, Pfingsten, Christi Himmelfahrt, Ostern and Karfreitag. Another religious-type holiday later in the year is Allerheiligen -- which I've always thought was much more (spiritually) justifiable than Halloween :) Of course Maifeiertag is also a public holiday and on top of this, if a public holiday falls on a Thursday (Christi Himmelfahrt and Fronleichnam this year), the research centre has an agreed day off on the Friday. Rest assured, though, that despite this hectic schedule of free days my commitment to acheiving my usually small output of work has not wavered!
By the way, the title of this post, when read in English, is roughly how you pronounce 'Feiertage' -- German for 'holidays'.
 Corpus Christi Feast. Celebrated 15th June this year.
 Pentecost. Celebrated 4-5th June this year.
 Ascension. Celebrated 25th May this year.
 Easter. Celebrated 16-17th April this year.
 Good Friday. Celebrated 14th April this year.
 All Saints. Celebrated 1st November.
 May Day. Celebrated umm ... I forget.