I have seen on quite a few websites that have a bit of text linked to the same page that it is on. In other words, if the page is called example.com/green-motorbikes on that page they will have the words green motorbikes linked essentially to itself.
Is there any good in this? Surely link juice isn't passed to the same page.
interesting question - I'm of the opinion that it doesn't add a lot of value in terms of getting that actual page ranked.
I do it sometimes linking directly to an image file (image sitting on the same page) so putting anchor text pointing to that image, and this may help in creating authority for the actual image in an image search for that particular keyword.
just linking to the page itself (entire content) may be bad for usability and that can outweigh any keyword or SE linking benefits you may derive.