I’m not sure how many of you know of Omniglot, a site all about languages and writing systems.
One of its features is lists of useful phrases in all sorts of languages, so you can look up how to say “Merry Christmas” in French or whatever – organised either by language (so you can see lots of useful phrases in French) or by phrase (so you can see how to say “Merry Christmas” in lots of languages).
One page they just added is a list of idioms in Welsh:
My favourite one is Mae e’n cadw draenog yn ei boced = “He’s tight with money” (“He keeps a hedgehog in his pocket”).
I got the mental image of a person putting his hand into his pocket to reach for his wallet, feeling the hedgehog, and withdrawing the hand again without being able to spend anything.
Incidentally, “they” as in Omniglot is mostly Simon Ager, a fluent Welsh speaker though not from birth. (His story of how he learned Welsh is here: http://www.omniglot.com/language/learning/welsh.htm .)