Intercultural E-Mail Classroom Connections - a clearinghouse for penpal, e-mail, and project exchanges.
Crayon allows the user to create a newspaper focused on specific categories of information and then have the paper delivered to yourself.
The Global Schoolhouse site facilitates projects making use of online collaborative learning.
Judi Harris designs for telecollaboration (communication projects).
EPal exchange - opportunities for email projects.
CyberKinds - publish original work of 7-12 yr. students. Writing.
ThinkQuest - This annual contest challenges teachers and students to create web projects that harness the power of the Internet. The archives form a library of educational materials for use in the classroom.