Or: bookplate. Personally, I hate it when people put bookplates in books. For me it is a real turnoff when I spot a second hand book and the previous owner glued one in. I feel the same when someone felt the need to write their name in a book. Why do people feel that need, I wonder? For collectors the books become worthless.
But… I do like the look of some bookplates. The art on them can be really nice. There is whole bunch of people who feel the same. Hence The Bookplate Society. Or this blog, by a self confessed ‘bookplate junkie’. The history behind these Ex Libris is actually quite interesting. You can learn about it here.