Jingū in Isë grants several kinds of ofuda, small sacred panels that are often said to hold the power of the kami. The most common, and best known, are the Jingū Taima, which Jinja Honchō would like every household in Japan to venerate. However, they also grant ofuda that you can only get by visiting Jingū in person — these are called Juyo Taima. An article in the August 1st issue of Jinja Shinpō reported on an interesting custom that relies on them.
The custom is maintained in an area of Isë City, fairly close to Jingū. At six road junctions that mark the edges of the area, Juyo Taima are enshrined. Originally there were four such locations, one each in the north, south, east, and west, but as the settled area grew two more were added to the south, so that there are now six.
The ofuda in question are called “Tsurugi Harai”, or “sword purification”, because they are vaguely sword shaped. (I am not committing myself to the reading of the Japanese name, because I couldn’t find an official source for the normal pronunciation. There are, as usual, multiple options.) These directly inherit the tradition of the ofuda distributed before the Meiji Revolution in 1868 (strictly, before the reform of Jingū Taima in 1872), and so the tradition may go back for centuries.
The ofuda are placed upright in a small box, which is about the same size and shape as the ofuda. This box is fixed on a pillar at the roadside; the pillar looks about as tall as an adult, with the box at the top, and a small roof over it. Normally, it seems that the ofuda are obtained by local residents on a rota, and that new ones are obtained from Jingū, both the Inner and Outer Sanctuaries, at fixed intervals. The new ofuda are, apparently, placed in the box in front of the older ones, so that several ofuda are found in each box. There is a surviving photograph of one of the pillars in 1937, and it looks very similar to the current one. (That photograph was taken to record a local custom, so we can certainly say that the practice is at least a century old, and almost certainly more.)
These ofuda are supposed to keep evil influences, such as illness, out of the area. This practice is not officially endorsed by Jingū, at least as far as the article says, but it is also clear that they do not object to it. This is a widespread attitude in Shinto — as long as you are treating the kami with respect, most priests do not mind much about the details of your veneration.