Well given it's March 17th, St. Patrick's day, 'Luck' was a great theme to chose for this week's Theme Thursday. Unfortunately I do not have anything Irish to share, but I do have some items related to 'luck'. Here are some vintage postcards featuring a good luck greetings. I normally don't take much notice of the fairly bland multiview ones, but on scanning in the first postcard was quite amused by the facial expression of the cat - looks like he's had some kind of shock.
Good Luck from Aberdeen, c.1959
Best of Luck from Newcastle-on-Tyne
Good Luck from Ramsgate, c.1954
Cheerio! Good Luck from Inverness
Hundreds more vintage postcards can be found on my web site