I try to never dog-ear my books. I use 'book marks'... which are usually in the form of scraps of paper, post-its, or a receipt. I generally use post-it's b/c I stick it to the page I'm on. But the main reason why I don't dog-ear books is because it tends to stay slightly bent. I used to dog-ear when I was younger but I noticed that the books I read over and over started having a lot of bent corners. So I switched to bookmarks. I don't use fancy bookmarks though... They always get lost.
i grew up dog earing my books, but with hardbacks and those borrowed from friends and libraries, i use a bookmark. i tend to use whatever scraps i can find for bookmarks, but i once had a roommate who would write down every book she had read whilst using that bookmark until there was no more space on it, in which case she started over.
I use a bookmark but I used to dog-ear. I just started using the bookmark because it's special to me. My dean gave it after I became one of the Top 5 students in my 8th grade class last year. Awesomeness. Haha.
I use a bookmark. Just the crummy ones that I get anytime I buy something from Chapters. As far as I'm concerned, dog earing is blasphemy. However when I buy a book with a jacket, the first thing I do is discard the jacket so ... I dunno maybe I'm a bit of a hypocrite.
When I see people on the bus dog-ear their pages I cry a little bit on the inside. I use a book mark. Traditionally it's the receipt from the bookstore where I bought the book. However, I have been known to use any bills that were nearby as a book mark forcing me to not pay that particular bill until I was done with the book (sorry again T-Mobile!)