Item one:

“Not my problem” in Polish is “nie moj cyrk, nie moje malpy.” Literally “not my circus, not my monkey”. (Hat-tip: Howard Tayler)

Item two:

“Silly season”, as in the summer period when the media loves frivolous stories even more than the rest of the time, is called sauregurkenzeit in German, which translates as “pickled cucumber season”. (Hat-tip: Wikipedia)

Any favourites of yours to add? The comments section awaits…