Probably one of the best known internet memes to-date, LOLcats are highly amusing pictures of cats with internet-speak captions. Updated multiple times during the day, there is no end to the number of LOLcat pictures.
Starting as just an artistic experiment in America, PostSecret is now a world-wide phenomenon bringing strangers together by expressing their secrets. Every week the website is updated with new batches of secrets posted from all over the world. The fifth book is set for release this year.
A book of crafts from the forum Craftster, which has been going strong for just over half a dozen years now (as of 2010). This book was written/compiled by Leah, who recently announced her departure from running the site after all that time.
Evidence that internet culture makes it into our everyday lives in various forms. Here in print format we see webcomic collections, blog spawn and other random items. Will be added to as I remember/find things. Feel free to make suggestions!