I ran on to an interesting article at Gourmet.com called No Cook Buttered Eggs. I've never really looked into preserving eggs. The Thousand Year Old eggs I've seen in the Asian Market scare me. I haven't yet been brave enough to try them. Don't worry, I'm sure I will eventually. But I haven't really had a need to preserve eggs yet. The leghorn chickens we had were prolific layers and we had fresh eggs coming out our ears. Then, the fox came, and we had to start out with new chickens. We decided to try some different breeds. The New Hampshire Red, Black Astrolopes and the Auracana's laid a plentiful amount of eggs, until the short days of winter arrived and we ran out of eggs for the first time in a very long time. Just a few months earlier, we were giving them away because we had more then we could consume, and I found myself wishing I had away to extend the life of those eggs so we wouldn't be completely out during the winter months.
In the County Cork, Ireland where butter is king (I'm sure you've heard of Kerry Irish butter) the Irish came up with a way to extend the life of eggs. They would gather the freshly laid eggs, still warm from the hen, and rub them in butter. Apparently this only works when the egg is freshly laid. The porous shell absorbs the butter and the egg will keep for much longer, although I'm not sure for how long, since I can't seem to find that information anywhere.
It's said that the egg takes on the taste of the butter and is most delicious when it's poached. According to Chef Darina Alien of Ballymaloe Cooking School the eggs were kept by the farmers wives and were theirs to sell for "hat pin money". This butter method was also a way to preserve enough eggs for the Easter Sunday egg buffet.
I'll have to spend some time out by the chicken coop this weekend and try this out. Wish me luck!