I like to consider myself someone who's helping to cultivate the next generation of practicing writers, particularly among the several precious preschoolers who call me "Aunt Erika." Recently, for example, I bought my niece (she's "three-and-a-half," as she'll tell you) a composition book at a drugstore around the corner from her apartment. It's now her special "story" book, in which Aunt Erika records, verbatim (or as close to verbatim as possible) stories we create together (I prompt with a line like "Once upon a time," or "and then the little girl said....", and my niece smiles and starts speaking). She loves watching me actually "write" her words on the page, and I love watching her become so engaged in the process of creating a story (as nonsensical as said story may be).
So I'm always looking out for online tips for helping children become avid readers and writers. Recently I found this great page at the National Writing Project. If you have prospective practicing writers in your life, you should check it out, too. It will lead you to some other excellent sites as well, such as this one from PBS.