"...a horseshoe is said to bring good luck. Many believe that to hang it with the ends pointing upwards is good luck as it acts as a storage container of sorts for any good luck that happens to be floating by, whereas to hang it with the ends pointing down, is bad luck as all the good luck will fall out" - wikipedia
One of my favorite "congratulations" gifts is a bottle of champagne with a horseshoe attached to the packaging. This photo is from 2004 when I first came up with this idea for someone starting their own company, but it works for many occasions.
Because we could all use a container for collecting a little extra luck!
p.s. I've gone to the local stables ( I know it sounds weird since I live in the city- but all the Michigan Ave carriage horses live very close to me) and they have just given me horseshoes.